For 13 terrifying seconds on 23 April this year, Turkey's largest city was shaken by a 6.2 magnitude earthquake. It was so strong that 151 people leapt from buildings in Istanbul in panic causing injuries, but no deaths.

But the Mayor, Ekrem Imamoglu, could not lift a finger to help the city he was first elected to run in 2019.

He was behind bars in a high-security prison complex in the district of Silivri, on the western edge of the city – ironically close to the epicentre.

Imamoglu is accused of a raft of corruption charges, which he strongly denies – "Kafkaesque charges" in his words.

Supporters say his only crime is being the greatest threat to Turkey's leader Recep Tayyip Erdogan, in presidential elections due by 2028.

Many of his fellow prisoners in Marmara jail - on the day of the earthquake - had also fallen foul of President Erdogan during his 22 years in power, some of them as peaceful protesters.

The jail is still widely known by its former name of Silivri. Hence the household phrase to explain why the speaker might be wary of criticising Erdogan: "Silivri is cold now."

Critics say that after Erdogan's early years as a Western-facing reformer, he has become a latter-day Sultan, dismantling human rights, cracking down on dissent and weaponising the courts.

The jailed mayor, leaders of his Republican People's Party (CHP), veteran lawyers, and student protesters are all appearing in the dock this month in separate cases.

"Erdogan has taken a huge step towards turning Turkey into a Russia-style autocracy," argues Gonul Tol, a senior fellow at the Middle East Institute (MEI) in Washington, who is from Turkey and now lives in the US.

"What he has in mind is a Turkey where the ballot box has no meaning… where he hand-picks his opponents."

In all, more than 500 people linked to the CHP have been arrested since last October.

Prosecutors accuse the mayor and his associates of taking bribes, rigging tenders, extortion, and having links to terrorism.

But the CHP - which is centrist and secular - argues that the detentions are politically motivated and aimed at silencing the opposition. The party denies the charges.

Some are asking why, as Turkish democracy comes under fire in full view, has the international community said little and done even less? Could it be that Erdogan has fingers in too many pies - including Russia, Ukraine, Syria, and Nato - for European leaders to want to pick a fight?

And is US President Donald Trump's willingness to look the other way on human rights giving Erdogan a freer hand?

'Overstepping the boundaries of justice'

Moments before his arrest in March, with hundreds of police on his doorstep, Mayor Imamoglu calmly carried on knotting his tie, while making a social media video for his supporters.

"We are facing great tyranny," he said, "but… I will not be discouraged."

He was composed and defiant - and "a mortal threat to Erdogan", according to Soner Cagaptay, director of the Turkish research programme at the Washington Institute in the US.

"He's charismatic, he's relatable, he's conservative like Erdogan, but also secular. He ticks so many boxes."

But he can tick far fewer in jail.

His arrest came just as the CHP – Turkey's largest opposition party - was poised to nominate him as their candidate for the presidency. (They did it anyway, after he was detained.)

Locking up Imamoglu sparked the biggest anti-government protests in more than a decade. It was mostly the young who surged onto the streets, members of Generation Erdogan who have known no other leader.

"It has reached the breaking point for most people," said one 21-year-old in Istanbul. "They have overstepped the boundaries of justice."

Another said this was "a direct attack on our democracy".

The government banned the demonstrations – which were largely peaceful - but could not stop them.

The turmoil in Istanbul played out in the shadow of a Roman aqueduct. Erdogan's legions of riot police took up positions under the arches, armed with batons, tear gas and rubber bullets.

One photo made front pages around the world: a lone protester dressed as a whirling dervish - in traditional costume plus gas mask – being pepper-sprayed by the police.

Hours after it was taken, the photographer, Yasin Akgul of the AFP news agency, was detained at home, his hands still stinging from tear gas. Several other leading photojournalists were also arrested.

Some 2,000 people were rounded up after the protests – many in pre-dawn raids. More than 800 of them were charged with taking part in "unauthorised demonstrations".

These days, getting arrested is "the easiest thing", according to Gonul Tol. "You just have to like a tweet or a Facebook post criticising Erdogan."

Student protester Esila Ayia, 22, was detained after holding up a poster calling the Turkish leader a dictator. (Insulting the president is a crime in Turkey.) If convicted, she could get four years in jail.

The arrests keep coming

Many Turks are feeling the chill, according to Berk Esen, associate professor of political science at Istanbul's Sabanci University, which has a liberal reputation. He claims there is "rampant pressure and oppression" of opposition figures in politics, civil society, academia and the media.

But he adds that Turkey is "not yet a fully fledged authoritarian regime… there is still some room for dissent".

Yet the arrests keep coming. More than 100 CHP members remain behind bars.

The president claims the CHP is "mired in corruption" with a network like "an octopus whose arms stretch to other parts of Turkey and abroad".

But Emma Sinclair-Webb of the campaign group Human Rights Watch sees a different octopus - the government itself.

It has "many, many, many, tentacles that go everywhere", she says. "There is a clear-sighted attempt by the government to go after critics and to go after the opposition.

"There is a complete loss of trust in the justice system. It's perceived more and more as highly politicised, and detention is being used to muzzle critics."

Members of the judiciary, prosecutors and judges themselves are "all the time looking up for instructions from above", she says.

The government says the judiciary is independent and impartial.

'He's a tough guy - very smart'

As Istanbul's mayor remains behind bars in Silivri, the international community remains focused elsewhere - chiefly on Israel's war in Gaza, and Russia's war in Ukraine.

The latter gives President Erdogan an edge, according to analysts.

He enjoys relatively good relations with Vladimir Putin, and Volodymyr Zelensky as well as Trump.

"I can't think of many other leaders who are in this position," says Berk Esen of Sabanci University. "I think in the international arena he likes to present himself as a dealmaker, in the room, shaking hands."

President Erdogan has had some success – for instance, helping to broker an agreement for Ukraine to resume grain exports through the Black Sea in July 2022, after they were halted by Russia's invasion five months earlier. And this year he hosted negotiators from Kyiv and Moscow for their first face-to-face talks since 2022.

"Everyone is praising his role in Russia and Ukraine," says Dr Tol. "Western leaders are looking to him to build European defence. And Trump doesn't care [what Erdogan does domestically], so he understands he can get away with it. "

She says Trump's return to the White House "has created an international context where regional autocrats feel empowered".

Dr Cagaptay, of the Washington Institute, says Erdogan has a freer hand because Trump has turned inwards, and the two leaders have "a special chemistry, going back to Trump's first term in office".

"I happen to like him, and he likes me," Trump has said of Erdogan. "He's a tough guy and he's very smart."

Erdogan is also well-placed geopolitically. Turkey's land mass lies partly in Asia, and partly in Europe, a bridge between two continents.

He holds plenty of other cards too - not least his leverage in neighbouring Syria. He backed the winning side there, supporting the Islamist rebels who overthrew President Bashar al-Assad in December.

He also leads the only Muslim nation in Nato, with the second largest army in the alliance, and a population of 85.6 million people. What happens here matters, for East and West.

"What Turkey is doing under Erdogan is leveraging its multiple identities very successfully," says Dr Cagaptay. "With the EU, I think Turkey is playing a middle power game very well…. whether it's about stabilising Syria or stabilising Ukraine after a ceasefire."

The sanctity of the ballot

Erdogan may be empowered - and enabled - but there is a limit, according to some analysts.

What he won't do is cancel the next presidential elections, according to Onur Isci, professor of history and international affairs at Kadir Has University in Istanbul.

"Historically the Turkish people have been acutely sensitive about the sanctity of the ballot and attempts to curtail it would provoke serious consequences," he says.

Turkish elections are generally free on the day, though far from fair beforehand.

The playing field is not level. Most mainstream media outlets are pro-government. Those that are not, come under strong pressure from the authorities.

During the last election in 2023, Erdogan hung on to power narrowly, winning 52.18% of the vote against the opposition candidate, Kemal Kilicdaroglu.

Recent polls have suggested he could be beaten next time by Imamoglu. But the mayor remains behind bars, facing several different trials, and the opposition will probably be forced to choose a different candidate.

As a two-term president, Erdogan, 71, is barred from running again, but he can solve that problem by calling early elections or bringing in a new constitution.

"I have no interest in being re-elected or running for office again," he said in May.

Mr Esen thinks otherwise. "He will run for the presidency as long as he is alive."

As the longest-serving leader in modern Turkey, he has a loyal base who want him to. Many conservative voters are grateful for the development brought by his Justice and Development Party (AKP) and for his promotion of Islam, in this secular republic.

Plenty of devotion was visible at a rally of the president's supporters before the last election.

One supporter, Ayse Ozdogan, had gone there early to hear her leader's every word, a crutch by her side.

"Erdoğan is everything to me," she said, with a broad smile. "We couldn't get to hospitals before, now we have transportation. He has improved roads. He has built mosques."

But what of his impact on Turkish democracy?

"It's hugely eroded but not dead," according to Ms Sinclair-Webb. "There is a very vibrant democracy, wedded to democratic principles and to elections."

The opposition too is very robust, she says.

Soner Cagaptay cites the example of a doner kebab seller, slicing meat on a spit.

"To me, that's like Turkish democracy under Erdogan. He's taken really thin slices over the past 20 years, and there's very little meat left."

But he says there is a lesson to take from the Erdogan era: "It takes a long time to kill a democracy."

We contacted the president's communication office for an official response but did not receive one.

In a report to the United Nations Human Rights Council, the Ministry of Foreign Affairs here said that Turkey has "stood firm to protect and promote human rights... and has continued its efforts at further compliance with international standards in law."

The report adds that they country "spares no effort to create favourable conditions for civil society, including human rights defenders".

That may ring hollow in the cells in Silivri.

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Contactless card payments are set to exceed £100 and potentially become unlimited under new proposals to allow banks and other providers to set limits.

The proposals from the Financial Conduct Authority (FCA) mean entering a four-digit PIN to make a card payment could become even more of a rarity for shoppers.

If approved, purchases which can cost more than £100 - such as a big supermarket shop, or large family meal in a restaurant - could be made with a tap of a card.

The move would bring cards in line with payments made through digital wallets on smartphones which have no restriction, and reflects the ongoing changes in the way people pay.

When contactless card payments were introduced in 2007, the transaction limit was set at £10. The limit was raised gradually, to £15 in 2010, to £20 in 2012, then to £30 in 2015, before the Covid pandemic prompted a jump to £45 in 2020, then to £100 in October 2021.

If approved, the latest plan could be put in place early next year.

Every rise has been met with concerns about theft and fraud, and the FCA said card providers would only permit higher-value contactless payments for low-risk transactions and would carry the burden if things went wrong.

However, the freedom for banks to raise or even scrap the contactless limit suggests the four-digit PIN could soon become relatively redundant.

The FCA has proposed the changes, despite the majority of consumers and industry respondents to a consultation favouring the current rules.

Some 78% of consumers who responded said they did not want any change to the limits.

The FCA said it did not expect any quick changes, but providers would welcome the flexibility over time when prices rise and technology advances. They could also give customers the option to set their own limits.

Fraud and theft fears

The idea of high-value payments being made with a tap of a card will raise concern that thieves and fraudsters will target cards.

Various protections are already in place. In addition to the £100 single payment limit, consumers are often required to enter a PIN if a series of contactless transactions totals more than £300, or five consecutive contactless payments are made.

The FCA's own analysis suggests raising the limits would increase fraud losses, but said detection was improving and would continue to get better.

It said any change would be reliant on providers ensuring payments were low-risk, through their fraud prevention systems.

Consumers would still get their money back if money was stolen by fraudsters, according to David Geale, from the FCA.

"People are still protected. Even with contactless, firms will refund your money if your card is used fraudulently," he said.

Many banks already allow cardholders to set a contactless limit of lower than £100, or switch it off completely, and the FCA expected this option to be made widely available.

It argued that time savings, less "payment friction", and a reflection of rising prices over time would make changes in the limits worthwhile.

Payment terminals would also need to be altered, as most are programmed to automatically refuse payments of more than £100 by card.

'I only use my phone to pay'

Smartphones already have an extra layer of security, through thumbprints or face ID. That allows people to pay without limits.

Nearly three-quarters of 16 to 24-year-olds regularly use mobile payments, according to industry research.

Near the appropriately named Bank Street in Sevenoaks, 24-year-old Demi Grady said she rarely bothered carrying her cards around anymore because she used her phone for everything.

"I was in London the other day, my phone died and I couldn't pay for stuff because I couldn't remember my card details," she said.

Her mum, Carrie, in contrast, uses her card when shopping.

"It would worry me more than be of benefit if they were to lose the limit of £100," she said.

Robert Ryan, who had just bought a "winter-ish jacket" at a Harveys Menswear on Bank Street said he did not regard entering a four-digit number when paying as a hassle. Instead it could be a useful budgeting tool.

"I feel more secure in what I'm buying and it does give me a bit of a prompt to make sure I'm not overspending on my tap-and-go," he said.

Richard Staplehurst, the owner of the store, said the majority of his customers were paying via a device.

He said that removing any obstacles to payment was great, but he did not want to be landed with a bill if a card was used fraudulently.

Stimulating the UK economy

The idea of removing the contactless limit was highlighted as one way the FCA was responding to the prime minister's call to regulators to remove restrictions to create more economic growth.

The government has been striving to improve the UK's economic performance, which has been slow for some time.

Other countries, such as Canada, Australia and New Zealand allow industry to set contactless card limits.

The FCA will consult on its proposals until 15 October.

One of the UK's top planning lawyers has said it would be "unlawful" for the government to grant planning permission for a Chinese "mega embassy" near the Tower of London.

The opinion, from Lord Banner KC, was submitted to the government on Monday, just ahead of the final deadline for those opposed to the scheme to have their say.

Opponents are stepping up their fight against China's plan to turn the historic Royal Mint Court into the largest embassy of any country in Europe.

Residents of flats forming part of the Royal Mint estate commissioned the legal document in a bid to derail the scheme, as they fear China, which is now their landlord, will ultimately force them to leave their homes.

Former housing secretary Angela Rayner called the scheme in last year, ensuring the final decision on the planning application would be taken by her and not Tower Hamlets Council.

One of the most contentious aspects of the planning application has been that sections have been 'greyed out' by China, with the intended use of the rooms in question obscured.

In August, Rayner had written to the Chinese side demanding they "explain the rationale and justification for each of the redactions".

Hong Kong dissidents, and other Chinese pro-democracy activists living in the UK, have expressed fears that these rooms could be used to hold and interrogate opponents of China's Communist regime.

China's response, given by planning consultants working on its behalf, was to clarify the use of some rooms, but to decline to do so for others saying, "the internal functional layout for embassy projects is different from other projects".

They pointed to the fact "the application for the new US embassy in Nine Elms did not disclose details of internal layouts".

In his opinion Lord Banner points to the fact that parts of Royal Mint Court are listed and says "it cannot tenably be said that the detail omitted by the redactions could have no possible planning consequences".

He gave examples of what needs to be assessed, including "the potential uses of the redacted rooms, any structural or safety (including but not limited to fire safety) implications of any physical structures".

Lord Banner also highlights that, no matter what assurances are given, the People's Republic of China (PRC) would "benefit from diplomatic immunity" for any activities occurring on that territory, giving "'carte blanche' in relation to what goes on in the rooms".

He called on Rayner's replacement, the new Housing Secretary Steve Reed, to be provided with unredacted plans, as planning permission "cannot lawfully be granted on the basis of the redacted plans".

A second area where there has been concern about the plans is that China wants to leave one section of the embassy site open to the public so people could view the ruins of a Cistercian abbey and also visit a Chinese heritage centre it hopes to build.

Earlier in the year, the Foreign Office and the Home Office had said this posed "specific public order and national security risks", because they feared that if there was a security or health alert in that paved forecourt, the emergency services would not be able to deal with it.

Any member of the public, including anti-China protestors, could walk into the area - but the police could not enter, as the land would be Chinese territory with "diplomatic inviolability".

They requested China enclose this section inside the embassy's security perimeter. Beijing has declined to do that.

Instead, it said it would agree, as a planning condition, that police or emergency services would be allowed to access the land, if necessary.

In his opinion, Lord Banner says this solution is not adequate, because it would "not be enforceable given the immunity conferred on the Embassy, the Ambassador, and other Embassy employees by virtue of... the Vienna Convention".

"In law the PRC's assurances are meaningless," he says, adding: "The PRC would be free in domestic and international law to U-turn on them at any time and there is nothing that planning conditions could do to stop this."

Despite Rayner's sudden departure, the Ministry of Housing, Communities and Local Government (MHCLG) has indicated her replacement Reed is still expected to make a decision on or before 21 October.

A MHCLG spokesperson said it would not be appropriate to provide ongoing commentary which could prejudice any final decision.

The Royal Mint Court Residents' Association said that with Lord Banner's opinion it had "shown why the Chinese Embassy at the Royal Mint cannot be approved".

They said: "The UK government should now put an end to the planning application once and for all, or face a humiliating judicial review."

Reed will have to weigh other issues alongside the planning questions, including serious security concerns.

Conservative politicians have said that if China is allowed to turn Royal Mint Court into its new embassy it could seek to tap into fibre optic cables running near the building that carry sensitive data for financial institutions in the City of London.

The Chinese Embassy in London has previously told the BBC that it "is committed to promoting understanding and the friendship between the Chinese and British peoples and the development of mutually beneficial cooperation between the two countries.

"Building the new embassy would help us better perform such responsibilities".

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The first of five Supreme Court justices who will decide the fate of the former Brazilian president, Jair Bolsonaro, has found the ex-leader guilty of plotting a coup.

But Bolsonaro will only be convicted if at least three out of the five justices find him guilty.

Justice Alexandre de Moraes said there was "no doubt" that there had been a coup attempt after Bolsonaro lost the 2022 presidential election to his left-wing rival, Luiz Inácio Lula da Silva.

Moraes also said that Bolsonaro had led the "criminal organisation" which he alleged was behind the attempted coup. Bolsonaro has denied all the charges.

If convicted, Bolsonaro - who governed Brazil from January 2019 to December 2022 - could face a lengthy sentence of more than 40 years in prison.

Read: What you need to know about Bolsonaro's coup plot trial

The charges against Bolsonaro are extremely serious and Justice Moraes - who had been widely expected to convict Bolsonaro - did not hold back in the summary of his decision.

The former president and his seven co-defendants - some of whom are top military officers - stand accused of trying to prevent President-elect Lula from taking up office.

The seven co-defendants have also denied the charges.

Speaking in court on Tuesday, Justice Moraes said there was plenty of evidence of a plot to kill Lula, his vice-presidential running mate, and Justice Moraes himself.

Moraes showed a document detailing the plan, codenamed Operation Green and Yellow Dagger, with key sections highlighted.

"This was written in the Brazilian government headquarters, at the same time that President Jair Bolsonaro was there," he said. He added that part of the plan had been printed out in the presidential palace.

According to investigators, the defendants failed to enlist enough support from the military for the plan to go ahead.

But Moraes argued that the defendants' efforts culminated in the storming of Congress, the Supreme Court and the presidential palace by thousands of Bolsonaro supporters on 8 January 2023 - one week after Lula was sworn into office.

Order was quickly restored and more than 1,500 people were arrested.

But, according to Moraes, Brazil had come close to descending into authoritarianism: "We are slowly forgetting that Brazil almost returned to its 20-year dictatorship because a criminal organisation, comprised of a political group, doesn't know how to lose elections."

"There is no doubt that the defendant, Jair Bolsonaro, held meetings with Armed Forces commanders to discuss the breach of constitutional norms," Moraes said.

The ex-president was not in court when Justice Moraes announced his guilty vote.

Bolsonaro's lawyers said their client was suffering from health problems. The 70-year-old was stabbed in the stomach while on the campaign trail in 2018 and has been having recurrent health issues resulting from the incident ever since.

His lawyers said that he followed the proceedings from his home in Brasília, where he is being kept under house arrest.

Because he is currently banned from using social media, we have not heard from him during the verdict stage of this trial but he has in the past said that the trial was politically motivated.

The former president alleges that it is designed to prevent him from standing in the 2026 presidential election.

However, he is already banned from running for public office until 2030 for spreading unfounded rumours about Brazil's voting system.

The trial has deepened divisions in Brazil, with supporters of Bolsonaro alleging that the five-member panel tasked with the case is biased.

They point to the fact that one of the justices was President Lula's personal lawyer while another served as Lula's justice minister.

Critics of Bolsonaro, on the other hand, say that Brazil's institutions need to act decisively when under attack. They point to the fact that democracy was only restored in 1985 after two decades of military rule to underpin their argument.

An Israeli-Russian researcher has been released after "being tortured for many months" by her Iraqi militia abductors, US President Donald Trump has announced.

In a post on Truth Social, Trump said: "I am pleased to report that Elizabeth Tsurkov, a Princeton student, whose sister is an American citizen, was just released by Kataib Hezbollah, and is now safely in the American embassy in Iraq".

Iraqi Prime Minister Mohammed Shia al-Sudani confirmed Ms Tsurkov's release shortly afterwards.

She had gone missing in Iraq during a research trip in March 2023 - Israeli Prime Minister Benjamin Netanyahu said several months later that she was being held by the Iran-backed Kataib Hezbollah.

In a post on X, Sudani said Ms Tsurkov's release was "a culmination of extensive efforts exerted by our security services over the course of many months".

He added that the security services on Tuesday were able to "uncover" the place the student had been held, before handing her over to the US embassy.

Ms Tsurkov entered Iraq on her Russian passport, Netanyahu's office said at the time.

According to Ms Tsurkov's website, her research focuses on the Levant - a historical term that refers to a large geographical region including present-day Israel, Syria and other areas - and "the Syrian uprising and civil war".

Kataib Hezbollah (Brigades of the Party of God) is a powerful Iraqi Shia militia that gets financial and military support from Iran. It was designated by the US as a terrorist organisation in 2009.

In Tuesday's post on Truth Social, Trump also said: "I will always fight for justice and never give up.

"Hamas, release the hostages, now!" he added, in a reference to those people seized by the Palestinian group during its deadly attack on Israel on 7 October 2023.

Israel has carried out a strike targeting the senior leadership of Hamas in Qatar's capital, Doha.

A Hamas official told the BBC that members of the Palestinian armed group's negotiating team were targeted during a meeting. It was not clear whether any of them were killed, but photos showed a badly damaged building in the northern Katara district.

The Israeli military accused the Hamas leaders of being directly responsible for the 7 October 2023 attack on Israel and of orchestrating the ensuing war in Gaza.

Qatar strongly condemned what it called the "cowardly Israeli attack that targeted residential buildings housing several members of the political bureau of Hamas".

"This criminal assault constitutes a blatant violation of all international laws and norms, and poses a serious threat to the security and safety of Qataris and residents in Qatar," a foreign ministry statement said.

The Gulf state - a key US ally in the region that is the location of a major American air base - has hosted the Hamas political bureau since 2012 and has served as a mediator in indirect negotiations between the group and Israel.

• Latest updates on Doha strike
• Israeli military orders all Gaza City residents to evacuate ahead of ground assault
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UN Secretary General António Guterres also condemned the strike, saying it was a "flagrant violation" of Qatar's sovereignty.

Israeli Prime Minister Benjamin Netanyahu's office stressed that what it called the "action against the top terrorist chiefs" of Hamas was a "a wholly independent Israeli operation".

"Israel initiated it, Israel conducted it, and Israel takes full responsibility," a statement said.

A senior Israeli official told Israeli media that the Hamas members targeted included Khalil al-Hayya, the chief negotiator and exiled Gaza leader, and Zaher Jabarin, the exiled West Bank leader.

"We are awaiting the results of the strike. There is a consensus among the political and security leadership," the official added.

On Monday, Israeli Defence Minister Israel Katz had warned Hamas leaders living abroad that they faced "annihilation" and Gaza would be destroyed if the group did not release its hostages and lay down its arms.

The Israeli military launched a campaign in Gaza in response to the Hamas-led attack on southern Israel on 7 October 2023, in which about 1,200 people were killed and 251 others were taken hostage.

At least 64,605 people have been killed in Israeli attacks in Gaza since then, according to the territory's Hamas-run health ministry.