A cyber hacker has pleaded guilty to stealing unreleased music from artists including British rock band Coldplay and US singer-songwriters Upsahl and Melanie Martinez.

Skylar Dalziel made about £42,000 by selling the tracks online, according to City of London Police.

Prosecutor Richard Partridge said she "selfishly used their music to make money for herself by selling it on the dark web".

The 22-year-old, of Winchester Gardens in Luton, admitted 11 copyright offences at Luton Crown Court and was sentenced to 21 months imprisonment, suspended for 24 months.

Det Con Daryl Fryatt, from the force's Police Intellectual Property Crime Unit, said: "Stealing copyrighted material for your own financial gain is illegal.

"It jeopardises the work of artists and the livelihoods of the people who work with them to create and release their music."

The thefts came to light when Sony Music Entertainment discovered a cloud account owned by Upsahl had been compromised and reported it to the International Federation of the Phonographic Industry (IFPI) in June 2021.

Forty unreleased tracks had been extracted and were being sold online, police said.

The IFPI and the Recording Industry Association of America identified an account on an online forum selling unreleased music from various artists and that account was linked to Dalziel.

Officers said they arrested Dalziel on 9 January 2023 and seized three drives which contained 291,941 music tracks.

They also found a spreadsheet which showed she had sold tracks to customers and her PayPal and bank accounts revealed she had received £42,049 from April 2021 to January 2023.

Some of this money was transferred to bank accounts in the US and City of London Police said it was working with Homeland Security Investigations to identify the people linked to the accounts.

Dalziel pleaded guilty to 11 counts of making for sale an article without licence of the copyright's owner, one count of transferring criminal property and three counts of acquiring/using/possessing criminal property.

She was also sentenced to 180 hours of unpaid work.

Det Con Fryatt said the sentencing "sends a clear message that we have the ability and tools to locate cyber criminals and hold them to account for their actions".

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A "cowardly" attacker who murdered a 64-year-old man with a single punch outside a pub has been jailed for life with a minimum term of 16 years.

Christopher Cooper, 39, from the Maritime Quarter in Swansea, punched Kelvin Evans, from Gorseinon, Swansea, once to the head.

The judge at Swansea Crown Court told Cooper Mr Evans's life was "senselessly and cruelly extinguished", and he had shown no remorse about the attack from behind outside The Station Hotel in Gorseinon, even boasting about the attack only taking one punch.

Mr Evans's 92-year-old mother Maureen said she looked at her son's picture every morning and night, and in tears told the court of her sadness.

Cooper and his partner Catherine Francis were at the pub - known locally as "The Gyp" - as were Mr Evans and his partner.

The judge said a perceived slight seemed to have been the trigger for the attack. Cooper had waited for Mr Evans to leave before hitting him.

After the attack in May the victim was immediately knocked unconscious and was taken to hospital, but his condition deteriorated, and he died a month later.

The judge told Cooper it was "a cowardly punch... totally unexpected" and it "would result in real serious injury" when the head would hit a hard surface.

Mr Evans was described by family as a kind man who would help anyone. He loved trips in his camper van Bella, often taking loved ones for days out.

Nephew Mark Jones said: "To lose him to such a cowardly attack has been nothing short of devastating.'"

He said Cooper and Francis' lies were "disrespectful and disturbing".

Cooper had previously admitted manslaughter but denied murder.

Judge Walters said Francis had lied throughout her evidence and shown no remorse.

She was previously convicted of assisting an offender and was sentenced to two years.

The Crown Prosecution Service said after the hearing that Francis was aware of the assault but did not call police.

Analysis of her phone showed she searched for hotels after the attack, and they were both arrested the next day at a service station.

A news summary from Apple has falsely claimed darts player Luke Littler won the PDC World Championship - before he has even played in the final.

On Friday morning, an iPhone notification based on a news story of Littler winning the semi-final of the PDC World Championship falsely made it appear that the BBC was reporting he had won the whole event.

The BBC previously complained to Apple when the feature generated a false headline about a high-profile alleged murder in the US.

Apple has been contacted for comment.

"It is essential that Apple fixes this problem urgently - as this has happened multiple times," said a BBC spokesperson.

"As the most trusted news media organisation in the world, it is crucial that audiences can trust any information or journalism published in our name and that includes notifications."

Littler, 18, has generated huge excitement in the darts world on his way to the final, which takes place on Friday evening.

Even though the notification appears to be directly from the BBC, it is in fact Apple Intelligence summarising three much longer headlines.

The other two stories in the summary, about the South Korean president and flu cases, were accurately summarised.

Apple Intelligence, which launched in the UK in December 2024, is intended to give users a simple round-up of all the alerts they have missed.

But the firm has run into some trouble since the feature launched, with inaccurate summaries of news stories and other notifications.

It prompted the journalist body Reporters Without Borders (also known as RSF) to call on Apple to axe its AI-powered summaries of news stories.

"The automated production of false information attributed to a media outlet is a blow to the outlet's credibility," said Vincent Berthier, the head of RSF's technology and journalism desk, in December.

He added it was "a danger to the public's right to reliable information on current affairs."

The latest notification glitch on Littler's semi-final win was received by a BBC News employee.

It is likely that most people's AI-generated summaries would be unique as different combinations of notifications are summarised depending on the device being used and the alerts coming through.

Apple Intelligence is only available on certain iPhones - those using the iOS 18.1 system version or later on recent devices (all iPhone 16 phones, the 15 Pro, and the 15 Pro Max). It is also available on some iPads and Macs.

The grouped notifications are marked with a specific icon, and users can report any concerns they have on a notification summary.

Apple has not outlined how many reports it has received.

US President Joe Biden has formally blocked the takeover of US Steel by a bigger Japanese company, saying foreign ownership could pose risks for national security.

The controversial decision comes a year after Nippon Steel first announced the $14.9bn (£12bn) deal, describing it as a lifeline for its smaller Pennsylvania-based rival.

But the transaction soon ran into political trouble, after leaders of the United Steelworkers union loudly opposed the deal, bringing political pressure to bear in a key state during the 2024 presidential election.

Biden decided to scrap the deal despite concerns by some advisors that it could damage Washington's relations with Tokyo, a key ally.

BBC News has contacted Nippon Steel and US Steel for comment.

Nippon Steel has previously denied that it planned to reduce production or cut jobs, while US Steel had warned that it might have to close plants without the investment that would come with a new owner.

Those concerns had been echoed by some workers and local politicians.

Other business groups said they feared rejecting the transaction would chill the climate for international investment in the US.

But Biden has voiced longstanding opposition to the deal. The transaction has also been criticised by President-elect Donald Trump and the incoming vice-president, JD Vance.

A US government panel charged with reviewing the deal for national security risks failed to reach a consensus by late December, leaving the decision to Biden, who was required to act within a 15-day deadline.

In his announcement on Friday he said maintaining US ownership was important to keeping the US steel industry and it supply chains strong.

"As I have said many times, steel production - and the steel workers who produce it - are the backbone of our nation," he said.

"That is because steel powers our country: our infrastructure, our auto industry, and our defense industrial base. Without domestic steel production and domestic steel workers, our nation is less strong and less secure."

Nippon Steel and US Steel have previously suggested they may pursue legal action against the government if the deal did not happen.

Prof Stephen Nagy, of the Department of Politics International Studies at the International Christian University in Tokyo, said this was a "political" decision, noting that the Biden administration from its start promised a "foreign policy for the middle class".

"This was a direct response and continuation of the Trump MAGA agenda of Making America Great Again," he said.

"The Biden administration couldn't appear weak on foreign businesses, whether it's an ally or adversary."

America's top doctor has called for risk warnings on alcoholic beverages, similar to the labels on cigarettes, following new research that links the drinks to seven types of cancer.

The advisory from US Surgeon General Vivek Murthy says the "majority of Americans are unaware of this risk" that leads to about 100,000 cases of cancer and 20,000 deaths annually in the US.

It would require an act of Congress to change the existing warning labels, which have not been updated since 1988.

Mr Murthy has also called for reassessing recommended limits for alcohol consumption and boosting education efforts regarding alcoholic drinks and cancer.

The Surgeon General, who is the leading spokesperson on matters of public health in the federal government, said that alcohol was the third most common preventable cause of cancer after tobacco and obesity.

"The direct link between alcohol consumption and cancer risk is well-established for at least seven types of cancer ...regardless of the type of alcohol (e.g., beer, wine, and spirits) that is consumed," Mr Murthy said in a statement.

This includes increased risk of throat, liver, throat, oesophageal, mouth, larynx and colon cancers.

The new report recommends health care providers should encourage alcohol screening and treatment referrals as needed, and efforts to increase general awareness should be expanded.

The warning labels are currently required to state that women who are pregnant should not drink alcohol due to birth defect risks. It also must state that "consumption of alcoholic beverages impairs your ability to drive a car or operate machinery, and may cause health problems".

Share prices of US-listed alcoholic beverage companies - including Diageo, the world's biggest spirits manufacturer - fell by up to 4% following the announcement.

US President Joe Biden has formally blocked the takeover of US Steel by a bigger Japanese company, saying foreign ownership could pose risks for national security.

The controversial decision comes a year after Nippon Steel first announced the $14.9bn (£12bn) deal, describing it as a lifeline for its smaller Pennsylvania-based rival.

But the transaction soon ran into political trouble, after leaders of the United Steelworkers union loudly opposed the deal, bringing political pressure to bear in a key state during the 2024 presidential election.

Biden decided to scrap the deal despite concerns by some advisors that it could damage Washington's relations with Tokyo, a key ally.

BBC News has contacted Nippon Steel and US Steel for comment.

Nippon Steel has previously denied that it planned to reduce production or cut jobs, while US Steel had warned that it might have to close plants without the investment that would come with a new owner.

Those concerns had been echoed by some workers and local politicians.

Other business groups said they feared rejecting the transaction would chill the climate for international investment in the US.

But Biden has voiced longstanding opposition to the deal. The transaction has also been criticised by President-elect Donald Trump and the incoming vice-president, JD Vance.

A US government panel charged with reviewing the deal for national security risks failed to reach a consensus by late December, leaving the decision to Biden, who was required to act within a 15-day deadline.

In his announcement on Friday he said maintaining US ownership was important to keeping the US steel industry and it supply chains strong.

"As I have said many times, steel production - and the steel workers who produce it - are the backbone of our nation," he said.

"That is because steel powers our country: our infrastructure, our auto industry, and our defense industrial base. Without domestic steel production and domestic steel workers, our nation is less strong and less secure."

Nippon Steel and US Steel have previously suggested they may pursue legal action against the government if the deal did not happen.

Prof Stephen Nagy, of the Department of Politics International Studies at the International Christian University in Tokyo, said this was a "political" decision, noting that the Biden administration from its start promised a "foreign policy for the middle class".

"This was a direct response and continuation of the Trump MAGA agenda of Making America Great Again," he said.

"The Biden administration couldn't appear weak on foreign businesses, whether it's an ally or adversary."

The stand-off started long before dawn. By the time we arrived in the dark, an army of police had pushed back suspended president Yoon Suk Yeol's angry supporters, who'd camped out overnight hoping to stop his arrest. Some of those I spoke to were crying, others wailing, at what they feared was about to unfold.

As dawn broke, the first officers ran up to the house, but were instantly thwarted - blocked by a wall of soldiers protecting the compound. Reinforcements came, but could not help. The doors to Yoon's house stayed tightly sealed, his security team refusing the police officers entry.

For several hours the investigators waited, the crowds outside growing more agitated - until, after a series of scuffles between the police and security officials, they decided their mission was futile, and gave up.

This is totally uncharted territory for South Korea. It is the first time a sitting president has ever faced arrest, so there is no rule book to follow - but the current situation is nonetheless astonishing.

When Yoon was impeached three weeks ago, he was supposedly stripped of his power. So to have law enforcement officers trying to carry out an arrest - which they have legal warrant for - only to be blocked by Yoon's security team raises serious and uncomfortable questions about who is in charge here.

The investigating officers said they abandoned efforts to arrest Yoon not only because it looked impossible, but because they were concerned for their safety. They said 200 soldiers and security officers linked arms, forming a human wall to block the entrance to the presidential residence, with some carrying guns.

This is arguably part of Yoon's plan, leveraging a system he himself designed. Before he declared martial law last month – a plan we now know he cooked up months earlier – he surrounded himself with close friends and loyalists, injecting them into positions of power.

One of those people is the current head of his security team, who took up the job in September.

But although alarming, this situation is not entirely surprising. Yoon has refused to cooperate with the authorities over this investigation, ignoring every request to come in for questioning.

This is how things reached this point, where investigators felt they had no choice but to bring him in by force. Yoon is being investigated for one of the most serious political crimes there is: inciting an insurrection, which is punishable by life in prison or death.

Yoon has also spurred on his supporters, who have gathered in force outside his residence every day since the arrest warrant was issued. He sent them a letter on New Years' Day thanking them for "working hard" to defend both him and the country.

Although most people in South Korea are upset and angry at Yoon's decision to impose martial law, a core of his supporters have stayed loyal. Some even camped overnight, in freezing temperatures, to try and stop police reaching his home.

Many told me this morning they were prepared to die to protect Yoon, and repeated the same unfounded conspiracy theories that Yoon himself has floated – that last year's election was rigged, and the country had been infiltrated by pro-North Korea forces. They held up signs reading "stop the steal", a slogan they chanted over and over.

Attention is also now on South Korea's acting President Choi Sang-mok, and how far his powers extend; whether he could and should sack the president's security chief and force the team to allow his arrest. The opposition party says police should be arresting anyone who stands in their way.

Although investigators have until 6 January to attempt this arrest again – this is when the warrant runs out - it is unlikely they will go in once more without changing their strategy or negotiating with the security team in advance. They will want to avoid a repeat of today's failure.

They also have to contend with the throngs of Yoon's supporters, who now feel victorious and empowered. They believe they are largely responsible for the authorities' climb down. "We've won, we did it," they have been singing all afternoon.

As their confidence grows, so will their numbers, especially with the weekend approaching.

US law enforcement is looking for clues to unravel the mystery behind the Tesla vehicle that exploded outside Trump International Hotel in Las Vegas earlier this week, giving seven people minor injuries.

The man who rented the Cybertruck - then drove it to the city and parked it in front of the hotel - has been identified as Matthew Alan Livelsberger, a 37-year-old active-duty US special forces soldier.

Police found his lifeless body inside the charred Tesla with a self-inflicted gunshot wound. They also found fuel cannisters and more than a dozen firework mortars in the bed of the vehicle.

On Thursday, there remained a heightened police presence at the hotel, located right off the busy Las Vegas strip. Yellow police tape cordoned off a small section of the hotel's entrance as employees worked to repair damage to the facade.

Authorities continue to work and piece together information, and many questions remain.

For example, it is unclear why Livelsberger rented the car - or if the perpetrator was intending to make a political statement ahead of Donald Trump's return to the White House later this month.

Why did Livelsberger drive to Las Vegas?

One of the biggest unanswered questions is why Livelsberger rented the Tesla and drove it more than 800 miles (1,300km) from Colorado to Las Vegas.

Las Vegas police said he rented the vehicle on 28 December in Denver. They were able to track his movements using photographs taken on the drive and information from Tesla's charging technology. He was the only one seen driving it, they said.

The vehicle arrived in the city on Wednesday morning, less than two hours before the explosion, police said.

Las Vegas Sheriff Kevin McMahill said on Thursday that a body inside the vehicle was recovered. It was burned beyond recognition, but the county's coroner used DNA and dental records to confirm that Livelsberger had been inside the Cybertruck at the time of the blast. He was found with a self-inflicted gunshot wound to the head.

"I'm comfortable calling it a suicide with a bombing that occurred immediately after," Sheriff McMahill said. He added that no motive for the incident had been established.

Was the explosion meant to be a political statement?

Another big question is whether the explosion was meant as a statement ahead of the change of US president later this month.

Police have not found any evidence that links the alleged perpetrator to specific political beliefs, but they said they were investigating whether the incident was tied to the fact that President-elect Donald Trump owns the hotel, or that Elon Musk runs Tesla.

Trump recently named Musk to co-lead a presidential advisory commission, the Department of Government Efficiency, after the two became close during Trump's campaign.

"It's not lost on us that it's in front of the Trump building, and that it's a Tesla vehicle," said Spencer Evans, an FBI agent based in Las Vegas, on Thursday.

"But we don't have information at this point that definitely tells us, or suggests, that (the incident) was because of a particular ideology," he said.

Was it related to the attack in New Orleans?

The explosion happened just a few hours after a man drove a pickup truck into New Year revellers on the crowded Bourbon Street in New Orleans, Louisiana, killing 14 people and injuring dozens of others.

That attacker has been identified as Shamsud-Din Jabbar, a 42-year-old US citizen who also served in the US Army.

President Joe Biden has said investigators are looking into whether the two incidents are linked, though so far nothing has been uncovered to suggest that is the case.

But the question continues to be fuelled by the apparent similarities between the two incidents and some biographical details of the drivers of both vehicles.

Both incidents happened in the early hours of New Year's Day. Both men served in the US armed forces - including at the Fort Liberty (formerly Fort Bragg) military base in North Carolina - and both completed a tour in Afghanistan. Both men also rented the vehicles they used through a mobile car rental application called Turo.

However, police have said there is no evidence the two men were in the same unit or served at the same time at Fort Liberty. Although both were deployed to Afghanistan in 2009, there is no evidence they served in the same province, location or unit.

In the New Orleans attack, police recovered an Islamic State (IS) group flag from the vehicle used by Jabbar. They added that he posted videos to social media moments prior claiming allegiance to the group. Police have determined that Jabbar was acting alone.

Meanwhile, in Las Vegas, there is no evidence that suggests that Livelsberger was motivated by IS, or that he and Jabbar had ever been in contact. Police have cautioned that the investigation remains active.

What is Livelsberger's background?

Livelsberger was a decorated special forces intelligence sergeant who was serving in Germany, but was on approved leave at the time of the incident.

His father told BBC's US partner CBS News that his son was in Colorado to see his wife and eight-month-old daughter.

He said he last spoke to his son at Christmas and that everything seemed normal.

The Daily Beast reported that Livelsberger was a "big" supporter of Trump. A senior law enforcement official who spoke with Livelsberger's family told the outlet that Livelsberger voted for Trump in November's election.

His uncle told The Independent that Livelsberger loved Trump "and he was always a very, very patriotic soldier, a patriotic American."

Israel has confirmed it is holding Gaza hospital director Dr Hussam Abu Safiya after earlier telling a local NGO that it was unaware of his case, sparking concern for his well being.

The Israel Defense Forces (IDF) statement said he was "currently being investigated by Israeli security forces" in person.

The statement did not offer an explanation for the confusion but repeated that he was suspected of being a "terrorist" and for "holding a rank" in Hamas, the armed Palestinian group at war with Israel in Gaza.

Dr Abu Safiya was arrested as the Israeli military forced patients and medical staff to leave Kamal Adwan hospital in northern Gaza last Friday, alleging the facility was a "Hamas terrorist stronghold".

On Thursday the IDF told Physicians for Human Rights Israel (PHRI) that it had "no indication of the arrest or detention of the individual in question".

The PHRI filed a petition with the Israeli High Court of Justice on Thursday, demanding Dr Abu Safiya's location be disclosed. It said the court had given the IDF a week to comply.

Meanwhile Amnesty head Agnès Callamard said Israeli authorities must "urgently disclose his whereabouts".

She said Israel had detained "hundreds of Palestinian healthcare workers from Gaza without charge or trial" and said they had been "subjected to torture and other ill-treatment and been held in incommunicado detention".

Israel denies mistreating detainees.

Dr Abu Safiya's family previously told BBC Arabic they believe he is being held at Sde Teiman military base in southern Israel, where Israeli forces have taken many detainees from Gaza for interrogation.

Whistleblowers have previously told the BBC and other international media of extremely harsh conditions for detainees there. Israel has said all detainees there are kept "carefully and appropriately".

The IDF ordered everyone inside Kamal Adwan hospital to leave last Friday morning, giving the hospital about 15 minutes to move patients and staff into the courtyard, medical staff told the BBC.

Beit Lahia, where the hospital is located, has been under a tightening Israeli blockade imposed on parts of northern Gaza since October. The UN has said the area has been under "near-total siege" as the Israeli military heavily restricts access of aid deliveries to an area where an estimated 10,000 to 15,000 people remain.

On Saturday, the IDF said it apprehended 240 combatants at Kamal Adwan and said Dr Abu Safiya was among medical staff taken for questioning.

Video footage showed him walking towards an Israeli armoured vehicle before being taken for interrogation. An Israeli military spokesperson confirmed the arrest that same day, saying the doctor had been transferred for questioning.

Dr Abu Safiya was previously arrested by Israeli forces during an earlier raid on the hospital in October, but was freed shortly afterwards. During that Israeli operation Dr Abu Safiya's 15-year-old son was killed in a drone strike. Footage from later that day showed him leading funeral prayers for his son in the hospital courtyard.

Israeli attacks on Gaza's healthcare facilities have prompted increasing condemnation.

On Tuesday the UN Human Rights Office says Israeli attacks on and around hospitals have pushed Gaza's healthcare system to "the brink of total collapse" and raised serious concerns about war crimes and crimes against humanity.

Israel's mission in Geneva said Israeli forces operated in accordance with international law and would "never target innocent civilians".

Israel launched a campaign to destroy Hamas in response to the group's unprecedented attack on southern Israel on 7 October 2023, in which about 1,200 people were killed and 251 others were taken hostage.

More than 45,580 people have been killed in Gaza since then, according to the territory's health ministry.

US President Joe Biden has formally blocked the takeover of US Steel by a bigger Japanese company, saying foreign ownership could pose risks for national security.

The controversial decision comes a year after Nippon Steel first announced the $14.9bn (£12bn) deal, describing it as a lifeline for its smaller Pennsylvania-based rival.

But the transaction soon ran into political trouble, after leaders of the United Steelworkers union loudly opposed the deal, bringing political pressure to bear in a key state during the 2024 presidential election.

Biden decided to scrap the deal despite concerns by some advisors that it could damage Washington's relations with Tokyo, a key ally.

BBC News has contacted Nippon Steel and US Steel for comment.

Nippon Steel has previously denied that it planned to reduce production or cut jobs, while US Steel had warned that it might have to close plants without the investment that would come with a new owner.

Those concerns had been echoed by some workers and local politicians.

Other business groups said they feared rejecting the transaction would chill the climate for international investment in the US.

But Biden has voiced longstanding opposition to the deal. The transaction has also been criticised by President-elect Donald Trump and the incoming vice-president, JD Vance.

A US government panel charged with reviewing the deal for national security risks failed to reach a consensus by late December, leaving the decision to Biden, who was required to act within a 15-day deadline.

In his announcement on Friday he said maintaining US ownership was important to keeping the US steel industry and it supply chains strong.

"As I have said many times, steel production - and the steel workers who produce it - are the backbone of our nation," he said.

"That is because steel powers our country: our infrastructure, our auto industry, and our defense industrial base. Without domestic steel production and domestic steel workers, our nation is less strong and less secure."

Nippon Steel and US Steel have previously suggested they may pursue legal action against the government if the deal did not happen.

Prof Stephen Nagy, of the Department of Politics International Studies at the International Christian University in Tokyo, said this was a "political" decision, noting that the Biden administration from its start promised a "foreign policy for the middle class".

"This was a direct response and continuation of the Trump MAGA agenda of Making America Great Again," he said.

"The Biden administration couldn't appear weak on foreign businesses, whether it's an ally or adversary."

There were more than 100 police officers and they were armed with a warrant - but South Korean authorities failed to arrest suspended President Yoon Suk Yeol after a six-hour deadlock outside his home.

That's how long the confrontation with Yoon's security team lasted as they formed a human wall and used vehicles to block the arrest team's path, according to local media.

It has been an unprecedented month for South Korean politics - Yoon's shocking yet short-lived martial law order was followed by an impeachment vote against him. Then came the criminal investigation, his refusal to appear for questioning and, earlier this week, a warrant for his arrest.

The right-wing leader still has a strong support base - and thousands of them turned up outside his home on Friday morning to oppose his arrest.

But, by many accounts, Yoon is now a disgraced leader - impeached by parliament and suspended from office, he awaits the decision of the constitutional court which can remove him from office.

So why has it proven so difficult for police to arrest him?

The men guarding the president

Although Yoon has been stripped of his presidential powers - after lawmakers voted to impeach him - he is still entitled to a security detail.

And those men played a key role in blocking the arrest on Friday.

The presidential security service (PSS) could have acted out of loyalty to Yoon or under "a misguided understanding of their legal and constitutional role", says Mason Richey, an associate professor at Seoul's Hankuk University of Foreign Studies.

Given that Yoon has been suspended, the PSS should be taking directions from acting President Choi Sang-mok. "They have either not been instructed by acting President Choi to stand down, or they are refusing his orders to do so," says Assoc Prof Richey.

Some experts believe the security officers were showing "unconditional loyalty" to Yoon, rather than the office itself. They point to the fact that the PSS's chief Park Jong-joon was appointed to the job by Yoon last September.

"It may well be the case that Yoon has seeded the organisation with hardline loyalists in preparation for precisely this eventuality," says US-based lawyer and Korea expert Christopher Jumin Lee.

And that Park's predecessor was former defence minister Kim Yong-hyun, who is accused of advising Yoon to impose martial law. He is currently being held for questioning as part of the criminal investigation into Yoon.

A risk of escalation

The "simplest" solution, Mr Lee says, is for acting president Choi to order the PSS to stand down in the interim.

"If he is unwilling to do so, that may be grounds for his own impeachment by the National Assembly," he added.

Choi, who is the finance minister, had stepped in to lead the country after lawmakers voted to impeach Yoon's first successor, Prime Minister Han Duck-soo.

This political stalemate also reflects the polarisation in South Korean politics - between those who support Yoon, and his decison to impose martial law, and those who oppose it. And the differences don't necessarily end there.

The vast majority of South Koreans agree that Yoon's declaration of martial law on 3 Dec was wrong and that he needs to be held accountable, says Duyeon Kim, an adjunct senior fellow at the Center for a New American Security - but they cannot agree on what accountability looks like.

"The actors involved disagree over process, procedure and their legal basis, which is adding to the current political uncertainty," she explains.

That uncertainty is also creating tense stand-offs like the one that unfolded on Friday in and outside Yoon's presidental residence, where his supporters have been camping out for days, leading to heated speeches and even skirmishes with police.

Law enforcement could return with more agents and use force but that would be "highly dangerous," Assoc Prof Mason said.

The PSS too is heavily armed, so arresting officers would be looking to avoid any escalation.

"What happens if the police show up with additional warrants calling for the arrest of PSS personnel, [the PSS] defy those warrants as well and then brandish their guns?" Mr Lee asks.

Police have now said they are investigating the PSS director and his deputy for obstructing them - so there could be more charges and arrest warrants coming.

The fallout from Yoon's martial law order is also a challenge for the Corruption Investigation Office (CIO) that is investigating him.

It has only been operating for four years. It was was created in response to public anger over former president Park Geun-hye who was impeached, removed from office and later jailed over a corruption scandal.

While South Korean presidents have been jailed before, Yoon is the first one to face arrest before he steps down.

Investigators have until 6 January to arrest Yoon before the current warrant expires.

They may attempt to arrest Yoon again over the weekend, although the weekend could pose a bigger challenge if the crowds of supporters grow. They can also apply for a new warrant and try to detain him again.

Given how far South Korea has now slid into uncharted territory, the uncertainty is likely to continue.

Additional reporting by Ewe Koh