At least three people have been killed and 20 others injured after Lisbon's famous Gloria funicular cable railway derailed and crashed, emergency services said.

In an earlier statement, the head of Portugal's Civil Protection Authority said that several people remained trapped at the scene and two people were in a serious condition.

Portuguese newspaper Observador reported that a cable came loose along the railway's route, causing it to lose control and collide with a nearby building.

The incident happened near the Avenida da Liberdade around 18:05 on Wednesday evening.

Footage shared widely on social media showed the yellow funicular overturned and almost entirely destroyed.

People could be seen fleeing the area on foot as what appears to be smoke smoke filled the air.

The Gloria Funicular is one of the most famous sights and tourist attractions in Lisbon. It was opened in 1885 and electrified three decades later.

Six people have been charged with terrorism offences relating to encouraging support for banned group Palestine Action, the Metropolitan Police said.

The charges relate to public gatherings held in London, Manchester and Cardiff that took place over the summer, as well as a planned demonstration this weekend in London.

The group were charged on Wednesday as part of an investigation being led by the Met's Counter Terrorism Command.

It comes ahead of a planned protest on Saturday where organisers have said they are expecting more than 1,000 people to attend a rally near Parliament.

• Met charge 47 more over alleged support for Palestine Action

The offences relate to allegedly arranging public demonstrations as well as managing 13 Zoom meetings, between July and August in support of the proscribed group.

All six were previously arrested on Tuesday at various locations in London, Cumbria and South Yorkshire. They are due to appear at Westminster Magistrates' Court on Thursday.

Another man was also charged on Tuesday as part of a connected investigation being led by Police Scotland.

Det Ch Supt Helen Flanagan said the charges had come about as a result of a "proactive investigation" into suspected activity linked to Palestine Action.

She added there are "potentially serious consequences" for those who are found guilty of an offence under the Terrorism Act.

"Palestine Action is clearly proscribed as a terrorist group, and those showing support for this particular group, or encouraging others to do so can expect to be arrested, investigated and prosecuted," she said.

On Tuesday, Campaign group Defend Our Juries said the arrests of its spokespeople were "scandalous" but said it still expected more than 1,000 people to attend the demonstration on Saturday where they would hold signs signs declaring "I oppose genocide. I support Palestine Action".

More than 700 people have been arrested by the Met since Palestine Action's proscription on 5 July.

Home Secretary Yvette Cooper banned the group under terrorism laws after paint was daubed on jets at RAF Brize Norton. Police said the act caused £7m of damage.

Lawyers for the group's co-founder, Huda Ammori, have argued that the ban breaches the right to free speech and has gagged legitimate protest.

The government says the ban is justified because it narrowly targets a group that was organising serious criminality.

Membership or support for Palestine Action is now an offence that can lead to up to 14 years in prison.

Last month, the group won permission to challenge the ban, with the case to be heard at the High Court in November.

The judge refused an appeal to temporarily lift the ban and it remains proscribed before a full review at the High Court in November.

The day they appeared he could hardly believe his eyes. Small boat after small boat bearing in from the Turkish side. "I have so many memories that are coming back to me now," says Paris Louamis, 50, a hotelier on the Greek island of Lesbos. "There were people from Syria, Afghanistan, many countries."

This was August 2015 and Europe was witnessing the greatest movement in population since the end of the Second World War. More than a million people would arrive in the EU over the next few months driven by violence in Syria, as well as Afghanistan and Iraq and elsewhere.

I witnessed the arrivals on Lesbos and met Paris Laoumis as he was busy helping exhausted asylum seekers near his hotel. "I am proud of what we did back then," he tells me. Along with international volunteers he provided food and clothing to those arriving.

Today the beach is quiet. There are no asylum seekers. But Paris is worried. He believes another crisis is possible. With the number of arrivals rising over the summer months, his country's migration minister has warned of the risk of an "invasion", with thousands arriving from countries such as Sudan, Egypt, Bangladesh and Yemen.

"Of course I worry. I can see the suffering of the people. They are not coming here but we see it on Crete (Greece's largest island) where people have come. So it is possible that with the wars more people will come here."

In 2015 I followed as the asylum seekers boarded ferries, trudged in the heat along railway lines, through cornfields, down country lanes and along highways, making their way up through the Balkans and onwards to Germany and Scandinavia.

The numbers entering Germany jumped from 76,000 in July to 170,000 the following month. On the last day of August the Chancellor Angela Merkel declared 'wir schaffen das' - we can do it - interpreted by many as extending open arms to the asylum seekers.

"Germany is a strong country," she said. "The motive with which we approach these things must be: we have achieved so much – we can do it! We can do it, and where something stands in our way, it has to be overcome, it has to be worked on."

But the high emotions of that summer, when crowds welcomed asylum seekers along the roads north, seem to belong to a very different time.

That optimistic proclamation soon became a political liability for Mrs Merkel. Political opponents and some European leaders felt the words acted as a magnet for asylum seekers to the EU. Within a fortnight the Chancellor was forced to impose controls on Germany's borders due to the influx of asylum seekers.

And a decade on, concerns over migration have become a major political issue in many European countries. The causes are complex and vary from country to country, but concerns around security, struggling economies and disillusionment with governing parties have all had a major role in shaping attitudes towards those who arrive who are fleeing war, hunger and economic desperation.

It has fuelled the rise of far right parties and seen centre and even left wing parties scramble to impose controls on migration, fearing electoral defeat by populist right-wingers. Data from the Atlas Institute of International Affairs shows how support for far right parties in Europe nearly doubled over the term of two electoral cycles to 27.6%.

Since 2015, when the UNHCR says over a million people entered Europe on asylum routes, there has been a dramatic drop in arrivals. But since 2016, the average number of people entering Europe has still been around 200,000 people a year. So far this year a total of 96,200 asylum seekers have been recorded arriving. So can tough new controls really further bring down the numbers trying to come to Europe? Or does global conflict and economic desperation make their continuing flow inevitable, with ebbs and flows in the numbers?

Hungary's tough stance

In Hungary, the far right government of Prime Minister Viktor Orban, has taken one of the toughest approaches to migration. Back in September 2015, I was present when Hungary's first fence was erected along the border with Serbia, and witnessed hundreds of people scrambling to cross into the EU before they could be shut out.

In Budapest, this week I met the country's minister for the EU, János Bóka, who said Hungary's approach has been vindicated by the restrictive measures now being put forward in the UK - where the government plan to make it harder for refugees to bring family members to the UK - as well as countries like Ireland, Denmark and Sweden.

"We feel vindicated not only because of what's going on in other countries in Europe. This is of course also a sign that we took the right path 10 years ago, that now we see most of the countries are doing what we have been doing for the past 10 years."

Hungary immediately returns people who arrive at the border without permission to enter. They can only apply for asylum in the Serbian capital Belgrade, or in Kyiv in war battered Ukraine.

Human rights lawyer Timea Kovács says this effectively makes it impossible to enter the EU via Hungary. "Basically there is no legal way to enter the Hungarian territory as a refugee," she asserts.

As a result Hungary is being fined one million Euros per day for breaching its responsibilities to asylum seekers under EU law. EU minister Bóka says the country is not about to change its policy. "If it is the price that we pay for the protection of our borders and maintaining peace and stability in Hungary, this is a price worth paying."

But even such restrictive measures haven't managed to entirely halt the entry of asylum seekers.

Austrian police told the BBC that there were between 20 to 50 people detected every day trying to enter their country illegally from Hungary. This is just the figure for those detected.

On a trip to the border with Serbia I heard the frustration of one group of Hungarian guards. We left the tar road and followed a patrol onto a dirt track into the forest. The trees closed over forming a natural tunnel. Bright sunlight gave way to shadows. The men in the vehicle ahead of us carried shotguns.

'Just one big circus'

Dressed in military camouflage Sándor Nagy and Eric Molner are citizen volunteers, paid by the state to patrol the Hungarian side of the border with Serbia.

"I feel sad and angry, and most of all, worried about what is coming," says Sandor. He believes Europe is failing to stop people from coming across its borders. "To be honest, what we experience here is basically just one big circus. What we see is that border defence here is mostly a show, a political performance."

We emerge into a clearing where a 12ft high border fence appears, topped with barbed wire, equipped with sensors and cameras to detect illegal crossings.

"They simply cut through it, and groups rush in at several points at once—this has been the same for years." The problem, he argues, is with organised crime, which is constantly one step ahead of the authorities. "This fence does not stop anyone in the long run … It delays the flow, but cannot stop it."

A deluge of abuses

With the growth of criminal trafficking has come a deluge of human rights abuses, according to the United Nations. People traffickers dump people in the Sahara desert; others crowd them onto unsafe boats. Some of those who get through find themselves being forced back into the desert by local security forces.

More than 32,000 people have died trying to reach Europe in the past 10 years - including 1,300 dead or missing this year.

According to the UN's International Organisation of Migration "much of this is happening in a situation of near complete impunity".

The summer of 2015 was not only a summer of welcome. It prompted immediate changes in the approaches of several European states. Not just with the erection of the fence in Hungary but, among several examples, the deployment of riot police in Croatia, and migrants being detained in Slovenia.

By March 2016 - six months after Mrs Merkel's statement - the EU had reached agreement with Turkey to keep migrants from crossing into Greece and Bulgaria.

Since then the EU has done deals with countries including Morocco, Tunisia, Libya and Egypt to prevent their countries being used as launch points to Europe.

Now, there are numerous well documented cases of asylum seekers being pushed back across EU borders by police and coast guards. Last January the European Court of Human Rights found Greece guilty of illegal and "systematic" pushbacks of asylum seekers to Turkey.

Gerasimos Tsourapa, a professor of international relations at the University of Birmingham, describes the policy of outsourcing the asylum issue as a dramatic change for Europe. "The idea that migration can be leveraged for money or aid or other concessions, which was fairly exceptional for Europe in 2016, has now become a pattern.

"Migration diplomacy is contagious. Once the deal is struck then the logic spreads."

There is also a paradox here, he says. "We are restricting asylum, we're keeping borders closed, but we also need to find labour migrants to fill shortages and help our national economy."

A changing Sweden

Persistent public concern has seen a rise in support for far right parties across the EU, even in places like Sweden, which historically prided itself as a welcoming nation for those fleeing persecution. The far right Sweden Democrats won 20.5 percent of the vote in the 2022 general election - making them the country's second largest party. In return for supporting a minority coalition government they have seen much of their anti-migration platform shape government policy.

Family re-unification for migrants has been made more difficult, as have conditions for permanent residency, and asylum quotas have been substantially reduced.

For the final leg of my journey I went to the western Swedish city of Karlstad, a picture postcard place on the banks of the River Klarälven, the longest waterway in Scandinavia.

Syrian refugee, Abdulmenem Alsatouf, 44, remembered the welcome he received here in 2015.

That has changed, he says. "At the beginning people treated us very well. But after a few years — and after the government changed — things shifted. They became more racist." He cites incidents of racist abuse, including one neighbour leaving a toy pig outside this devoutly Muslim family's home.

I first met Abdulmenem and his family ten years ago as they were trying to reach Europe from Turkey. I remember their hope for a new life. Now his wife Nour says she would prefer to be in Syria. "They look at us as if we only came here to take their money or live off their aid. But that's not true. When I first arrived, I studied Swedish for two years, I learned the language, I finished school. Then I went to work — cleaning, kitchens, childcare. I pay taxes here, just like anyone else. I'm part of this society."

Why has Swedish public opinion shifted to the right on migration? One of the more frequently cited reasons in local media and by politicians is crime, specifically the rise of organised crime, with young perpetrators used to commit extreme violence. Since 2013 the rate of gun crime in the country has more than doubled.

People born abroad, and their children born in Sweden, are over-represented in crime statistics. But Sweden's foreign ministry warns against a simplistic analysis of figures. It says low levels of education, unemployment, social segregation and refugee's war trauma are all causes - not the fact of being a migrant.

Outside the local cultural museum, where he and his apprentice were busy painting the walls, I met Daniel Hessarp, 46, who is among the 60% of Swedes that opinion polls record as being concerned about crime. "We see the statistics of the crimes, who does it and such. So, there you have the answer. We didn't have this before in Sweden.

The apprentice, Theo Bergsten, 20, said he wasn't opposed to immigration because "you learn from, they learn from you…so it's really nice also." But he said the growth in crime was a "sad part" of the story.

Maria Moberg, a sociology lecturer at the University of Karlstad, says social media has allowed the far right's message to thrive and find new support among those who feel excluded from society.

"Sweden Democrats are very open with [us] - they don't want any asylum seekers. They actually want people to leave Sweden. And the whole government is sort of setting the agenda for being a hostile country. It's more acceptable now to not be welcoming."

Graves marked 'Unknown'

Back on Lesbos, I went to visit a place I have come to know over many years of reporting migration issues there. About 30 minutes drive from the Mytilene airport, in the middle of some olive groves, are the graves of asylum seekers who have died trying to reach here, or in the refugee camps set up after 2015. Numerous graves are simply marked 'Unknown', the last resting place of those who believed Europe would offer them a better life.

When I visited there were three fresh graves, and a fourth open waiting for a burial to take place. It is a sobering reminder that desperate people will keep trying to reach Europe, despite the enormous risks.

So far this year the numbers of asylum seekers detected trying to reach Europe is down by 20 percent. The numbers may surge and fall, but the global crises that drive migration are not going to disappear. That is the fundamental challenge for politicians, whatever party is in power.

Top image credit: Beata Zawrzel/NurPhoto via Getty Images

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One of Lisbon's most iconic tourist attractions, the Gloria funicular, derailed and crashed on Wednesday evening.

At least 15 people have been killed and 18 more injured, some critically, local authorities have said.

It is not yet clear what caused the carriage to derail.

Here's everything we know so far:

What have authorities said?

The crash occurred at around 18:05 on Wednesday, near Lisbon's Avenida da Liberdade, according to local authorities.

More than 60 emergency service personnel and 22 vehicles were deployed to the scene.

Officials said it was too early to determine the cause of the incident. However, Portuguese newspaper Observador reported that a cable came loose along the railway's route, causing it to lose control and collide with a nearby building.

Images and footage from the scene the showed an overturned yellow carriage, which appeared almost entirely destroyed.

People could be seen fleeing the area on foot as smoke engulfed the cobbled street.

• At least 15 dead after Lisbon's historic funicular derails

What do we know about the casualties?

Portugal's emergency medical service authority said at least 15 people have been been killed and 18 others injured.

Five of those injured were in a serious condition, it said. The remaining thirteen, which included a child, sustained minor injuries.

Lisbon's mayor, Carlos Moedas, said the victims had been taken to hospital.

Some of those killed were foreign nationals, authorities said.

Several people trapped at the scene have since been freed, the medical authority said.

Who was onboard?

The Gloria funicular can carry up to 43 passengers and is extremely popular with tourists.

It is not known how many people were onboard at the time of the collision, however.

What is the Gloria funicular and how does it work?

A funicular is a type of railway system that allows travel up and down steep slopes.

In Lisbon, funiculars are among the most sought after tourist attractions. The bright yellow vehicles are a crucial means of navigating the city's steep, cobbled streets.

The Gloria funicular - the railway on which the collision took place - was opened in 1885 and electrified three decades later.

It travels some 275m (900ft) from Restauradores, a square in the centre of Lisbon, up to the picturesque streets of Bairro Alto. The journey takes just three minutes to complete.

Unlike traditional funiculars, the two cars on the Gloria funicular are powered by electric motors.

They are attached to opposite ends of a haulage cable meaning that as one travels downhill, its weight lifts the other, allowing them to ascend and descend simultaneously.

'Lisbon is in mourning'

Lisbon Mayor Carlos Moedas has declared three days of municipal mourning for the victims of the incident.

Posting on X, he said: "I extend my heartfelt condolences to all the families and friends of the victims. Lisbon is in mourning."

Spain's Prime Minster Pedro Sánchez said he was "appalled by the terrible accident".

"All our affection and solidarity with the families of the victims and with the Portuguese people in this difficult moment," he wrote in a statement on X.

Portuguese President Marcelo Rebelo de Sousa said he "deeply regrets" the "fatalities and serious injuries" caused by the crash.

In a statement, he expressed his "condolences and solidarity with the families affected by this tragedy" and hoped for clarity around the incident from authorities soon.

Pedro Bogas from Carris, the Lisbon Tramways Company, told reporters it was a "very a sad day, not just for the victims but also for their families".

"We have strict protocols, excellent professionals for many years, and we need to get to the bottom of what happened," he added.

European Commission President Ursula von der Leyen wrote on X: "It is with sadness that I learned of the derailment of the famous Elevador da Glória. My condolences to the families of the victims."

One of Lisbon's most iconic tourist attractions, the Gloria funicular, derailed and crashed on Wednesday evening.

At least 15 people have been killed and 18 more injured, some critically, local authorities have said.

It is not yet clear what caused the carriage to derail.

Here's everything we know so far:

What have authorities said?

The crash occurred at around 18:05 on Wednesday, near Lisbon's Avenida da Liberdade, according to local authorities.

More than 60 emergency service personnel and 22 vehicles were deployed to the scene.

Officials said it was too early to determine the cause of the incident. However, Portuguese newspaper Observador reported that a cable came loose along the railway's route, causing it to lose control and collide with a nearby building.

Images and footage from the scene the showed an overturned yellow carriage, which appeared almost entirely destroyed.

People could be seen fleeing the area on foot as smoke engulfed the cobbled street.

• At least 15 dead after Lisbon's historic funicular derails

What do we know about the casualties?

Portugal's emergency medical service authority said at least 15 people have been been killed and 18 others injured.

Five of those injured were in a serious condition, it said. The remaining thirteen, which included a child, sustained minor injuries.

Lisbon's mayor, Carlos Moedas, said the victims had been taken to hospital.

Some of those killed were foreign nationals, authorities said.

Several people trapped at the scene have since been freed, the medical authority said.

Who was onboard?

The Gloria funicular can carry up to 43 passengers and is extremely popular with tourists.

It is not known how many people were onboard at the time of the collision, however.

What is the Gloria funicular and how does it work?

A funicular is a type of railway system that allows travel up and down steep slopes.

In Lisbon, funiculars are among the most sought after tourist attractions. The bright yellow vehicles are a crucial means of navigating the city's steep, cobbled streets.

The Gloria funicular - the railway on which the collision took place - was opened in 1885 and electrified three decades later.

It travels some 275m (900ft) from Restauradores, a square in the centre of Lisbon, up to the picturesque streets of Bairro Alto. The journey takes just three minutes to complete.

Unlike traditional funiculars, the two cars on the Gloria funicular are powered by electric motors.

They are attached to opposite ends of a haulage cable meaning that as one travels downhill, its weight lifts the other, allowing them to ascend and descend simultaneously.

'Lisbon is in mourning'

Lisbon Mayor Carlos Moedas has declared three days of municipal mourning for the victims of the incident.

Posting on X, he said: "I extend my heartfelt condolences to all the families and friends of the victims. Lisbon is in mourning."

Spain's Prime Minster Pedro Sánchez said he was "appalled by the terrible accident".

"All our affection and solidarity with the families of the victims and with the Portuguese people in this difficult moment," he wrote in a statement on X.

Portuguese President Marcelo Rebelo de Sousa said he "deeply regrets" the "fatalities and serious injuries" caused by the crash.

In a statement, he expressed his "condolences and solidarity with the families affected by this tragedy" and hoped for clarity around the incident from authorities soon.

Pedro Bogas from Carris, the Lisbon Tramways Company, told reporters it was a "very a sad day, not just for the victims but also for their families".

"We have strict protocols, excellent professionals for many years, and we need to get to the bottom of what happened," he added.

European Commission President Ursula von der Leyen wrote on X: "It is with sadness that I learned of the derailment of the famous Elevador da Glória. My condolences to the families of the victims."

Victims of Jeffrey Epstein gave emotional accounts of sexual abuse on Wednesday, as they spoke on the steps of the US Capitol and called for lawmakers to release more files about the convicted sex offender.

One of the women, Lisa Phillips, said the group had begun compiling a confidential list of Epstein associates who they say were involved in abuse

"We will confidentially compile the names we all know were regularly in the Epstein world," she said. "It will be done by survivors, and for survivors."

The event was organised by US lawmakers who are calling for more files from the Epstein investigation to be released publicly.

During the two-hour news conference, nine female Epstein accusers detailed their experiences and abuse at the hands of the disgraced financier.

Ms Phillips urged the Department of Justice to release all the documents and information it has from the investigation, adding that many victims were afraid of repercussions if they went public with names themselves.

A lawyer for the accusers added that they are scared of being sued or attacked because "nobody protected them the first time".

Marina Lacerda, speaking publicly for the first time, said she worked for Epstein from the age of 14 until she was 17, when the disgraced financier determined she was "too old".

"I was one of dozens of girls that I personally know who were forced into Jeffrey's mansion... in New York City when we were just kids," she said.

"A friend of mine in the neighbourhood told me that I could make $300 to give another guy a massage," Lacerda said, while becoming visibly emotional. "It went from a dream job to the worst nightmare."

Annie Farmer, who is now 46, said she was taken to New Mexico aged 16 to spend a weekend with Epstein. Her sister was also flown there and reported the abuse, she said, but nothing was done.

"We still do not know why that report wasn't properly investigated, or why Epstein and his associates were allowed to harm hundreds, if not thousands, of other girls and young women," she said.

Chauntae Davies addressed a question about the relationship between Trump and Epstein, saying the sex offender's "biggest brag forever was that he was very good friends with Donald Trump".

"He had a framed picture of him on his desk, with the two of them," she said.

Trump was a friend of Epstein, but said they fell out in the early 2000s because the financier poached employees from the spa in Trump's Florida golf club.

"This is a Democrat hoax that never ends," Trump told reporters in the Oval Office on Wednesday when asked about the nearby news conference.

He said "nobody is ever satisfied" with the files that have been released, adding that the call for more releases is a distraction from his record in office.

"Really I think it's enough," Trump said.

On Tuesday evening, 33,000 pages and several videos were made public by the House Oversight Committee, which has subpoenaed the Justice Department and Epstein estate. Most of those, however, were already in the public domain.

The top Democrat on the committee, Robert Garcia, said: "Don't let this fool you".

"After careful review, Oversight Democrats have found that 97% of the documents received from the Department of Justice were already public. There is no mention of any client list or anything that improves transparency or justice for victims," he said.

It is believed that the Department of Justice has about 100,000 pages of material on Epstein.

The release on Tuesday followed last month's publication of the US Department of Justice interview with Ghislaine Maxwell, who was an accomplice of Epstein.

In the transcripts - which run to 300 pages, some heavily redacted - Maxwell said that while she believed Trump and Epstein were friendly "in social settings", she didn't think they were close friends.

Two members of the House, Republican Thomas Massie of Kentucky and Democrat Ro Khanna of California, are trying to force a vote on compelling the justice department to release all documents in the case.

They were gathering signatures on Wednesday, with dozens of representatives agreeing to back the move. They will need 218 signatures to force a vote, meaning two Republicans would need to support it.

"It's shameful this has been called a hoax. This is not a hoax," Massie said. "There are real victims to this criminal enterprise and the perpetrators are being protected because they are rich and powerful."

The White House and Republican congressional leaders oppose the release of all of the files, saying that it could expose the identities of victims who do not want to go public.

A strike carried out by US forces on a boat in the Caribbean Sea - which the White House says killed 11 drug traffickers - may have violated international human rights and maritime law, legal experts have told BBC Verify.

President Donald Trump announced on Tuesday that US forces destroyed a vessel which he said had departed from Venezuela. He said the boat was operated by the Tren de Aragua cartel and was carrying drugs bound for the US.

US defence officials have so far declined to offer details on the strike, footage of which Trump shared on Truth Social, including what legal authority they relied upon to justify it.

BBC Verify reached out to a range of experts in international and maritime law, with several saying that US may have acted illegally in attacking the vessel.

The US is not a signatory to United Nations Convention on the Law of the Sea, but the US military's legal advisors have previously said that the US should "act in a manner consistent with its provisions".

Under the convention, countries agree not to interfere with vessels operating in international waters. There are limited exceptions to this which allow a state to seize a ship, such as a "hot pursuit" where a vessel is chased from a country's waters into the high seas.

"Force can be used to stop a boat but generally this should be non-lethal measures," Prof Luke Moffett of Queens University Belfast said.

But he added that the use of aggressive tactics must be "reasonable and necessary in self-defence where there is immediate threat of serious injury or loss of life to enforcement officials", noting that the US moves were likely "unlawful under the law of the sea".

Are US strikes on alleged cartel members legal?

Experts have also questioned whether the killing of the alleged members of the Tren de Aragua cartel could contravene international law on the use of force.

Under Article 2(4) of the UN charter, countries can resort to force when under attack and deploying their military in self-defence. Trump has previously accused the Tren de Aragua cartel of conducting irregular warfare against the US, and the state department has designated the group as a Foreign Terrorist Organisation.

But Prof Michael Becker of Trinity College Dublin told BBC Verify that the US actions "stretches the meaning of the term beyond its breaking point".

"The fact that US officials describe the individuals killed by the US strike as narco-terrorists does not transform them into lawful military targets," he said. "The US is not engaged in an armed conflict with Venezuela or the Tren de Aragua criminal organization."

"Not only does the strike appear to have violated the prohibition on the use of force, it also runs afoul of the right to life under international human rights law."

Prof Moffett said that the use of force in this case could amount to an "extrajudicial arbitrary killing" and "a fundamental violation of human rights".

"Labelling everyone a terrorist does not make them a lawful target and enables states to side-step international law," he said.

Notre Dame Law School Professor Mary Ellen O'Connell told BBC Verify that the strike "violated fundamental principles of international law", adding: "Intentional killing outside armed conflict hostilities is unlawful unless it is to save a life immediately."

"Sometimes armed groups waging war against governments deal in drugs to pay for their participation in conflict. There is no evidence the gang President Trump targeted is such a group."

But US officials have been quick to defend the strike. Republican Senator Lindsay Graham wrote on X that the strike was the "ultimate - and most welcome - sign that we have a new sheriff in town".

His fellow Republican senator, Bernie Moreno from Ohio, wrote: "Sinking this boat saved American lives. To the narco traffickers and the narco dictators, you'll eventually get the same treatment."

A White House official told BBC Verify that Trump had authorised the strike on the boat, which they said was crewed by Tren de Aragua members, after it left Venezuela. The official added that the president was committed to using all means to prevent drugs reaching the US.

The Pentagon declined to offer further comment or share the legal advice it obtained before carrying out the strike.

Can Trump launch attacks without Congressional approval?

Questions have also been raised as to whether the White House complied with US law in authorising the strike. The US constitution says that only Congress has the power to declare war.

However, Article II - which lays out the president's powers - says that "the president shall be Commander in Chief of the Army" and some constitutional experts have suggested that this grants the president the power to authorise strikes against military targets. Trump administration sources have previously cited this provision when defending US strikes on Iran.

But it is unclear whether that provision extends to the use of force against non-state actors such as drug cartels.

• Trump says 11 killed in US strike on drug-carrying vessel from Venezuela
• US offers $50m reward for arrest of Venezuelan leader Nicolás Maduro
• Venezuela's ex-spy chief pleads guilty to narco-terrorism charges

Rumen Cholakov, an expert in US constiutional law at King's College London told BBC Verify that since 9/11, US presidents have relied on the 2001 Authorization of Use of Military Force Act (AUMF) when carrying out strikes against groups responsible for the attacks.

"Its scope has been expanded consistently in subsequent administrations," he added. "It is not immediately obvious that drug cartels such as Tren de Aragua would be within the President's AUMF powers, but that might be what "narco-terrorists" is hinting at."

Questions also remain as to whether Trump complied with the War Powers Resolution, which demands that the president "in every possible instance shall consult with Congress before introducing United States Armed Forces into hostilities".

How did the US conduct the strike?

It is unclear what method the US used to launch the attack. Trump did not offer details in his news conference in the Oval Office and the Department of Defense has failed to offer further information.

In Venezuela President Maduro has yet to respond to the US strikes, but his Communications Minister Freddy Ñáñez has suggested that the footage released by the White House may have been generated using AI. In a post to X, he suggested that water in the video "looks very stylized and unnatural".

BBC Verify has run the clip through SynthID - Google's AI detection software - and found no evidence that the footage is fake.

The strikes come amid reports that the US has deployed several naval warships to the region in support of anti-narcotics operations against Venezuela.

We've not been able to track all of these vessels. But using information from publicly-available onboard trackers, and videos on social media, we've potentially identified four of them in the region.

A ship identifying itself as the USS Lake Erie - a guided missile cruiser - last transmitted its location in the Caribbean Sea on 30 August, east of the Panama Canal on 30 August.

Two others identifying themselves as the USS Gravely and USS Jason Dunham last transmitted their locations in mid-August, at the American base in Guantanamo Bay. A fourth, the USS Fort Lauderdale, transmitted its location north of the Dominican Republic on 28 August.

Trump - who has long sought to oust Venezuela's President Nicolás Maduro - has authorised a US$50m reward for any information leading to his arrest. The Venezuelan leader claimed victory in last year's elections, widely viewed as rigged by international observers.

Additional reporting by Lucy Gilder.

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