The 25-year-old was arrested on Thursday afternoon in Westminster, central London, on suspicion of preparing terrorist acts.

Counter Terrorism Policing (CTP) searched two properties in the area as part of the investigation.

A second man, 26, who is a UK national, has also been questioned under caution, police said.

Five men in their 20s, who were arrested on Sunday, are still on police bail while the investigation continues.

Vicki Evans, senior national coordinator for counter terrorism policing, said: "The investigation into circumstances surrounding events in Gloucestershire is hugely complex, and our specialist teams are interrogating multiple lines of enquiry.

"As we've made clear, we're looking at all possible angles - including possible foreign state involvement.

"I'd like to thank the public for their continued support and patience whilst we work through this investigation."

The five previously arrested men - four of whom live in Westminster and one in Camden, north London - were detained early on Sunday after reports of "three suspicious vehicles" in the village of Whelford, near RAF Fairford.

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After the decision to release the five arrested suspects on bail, US President Donald Trump expressed surprise at the development.

In response, counter terror police said it was an "investigative decision" that was "grounded in experience and careful considerations of policing powers".

They added that no explosives were found in the vehicles, but a quantity of petrol was recovered.

Officers said they were considering whether a foreign state was involved in the incident. Prime Minister Andy Burnham added on Wednesday that Iran may have been involved.

Earlier on Thursday, Israeli Prime Minister Benjamin Netanyahu claimed Israel handed Britain intelligence about the suspected terror plot.

RAF Fairford has been used in recent months by US bombers after former prime minister, Sir Keir Starmer, granted the US permission to use British bases for "defensive" strikes against Tehran during the Middle East war.

Christa Pike, 50, convicted of murdering a schoolmate three decades ago, was due to be executed after the US Supreme Court overturned an earlier reprieve that had been ordered just an hour before her sentence was initially scheduled to be carried out in Nashville on Wednesday.

The state proceeded with the planned execution. However, Pike's lawyers filed an emergency motion to halt and stay the execution, claiming she was still alive after both syringes of lethal injection chemicals had been administered.

Pike's lawyers said she had "not lost consciousness, and still has a heartbeat", adding that she was "audibly snoring".

They said the curtains to the death chamber had "gone down twice", and, as part of the motion, requested "immediate medical care".

The Tennessee Department of Correction said she had been transported from the Riverbend Maximum Security Institution to "an off-site medical facility".

Officials added that "every step of the state's lawful, established execution protocol approved by the attorney general's office" had been followed.

'It was cruel and it was torturous'

In a press conference on Thursday, Pike's lawyers, Randy Spivey and Stephen Ferrell, said that she was receiving "life-saving medical care".

"Last night was not just inefficient; it was cruel and it was torturous," Mr Spivey said, adding that at least seven needles were used to administer the lethal injection into Pike's left arm over the course of an hour.

He said that at least one of the needles looked bent when it was pulled from Pike's arm, and that she was "continuing to show signs of life" after at least two full doses of the lethal drug, pentobarbital.

The lawyer also noted that the members of the media could hear her "breathe and choke and struggle while the state worked in secrecy", and that five minutes after the second dose, "it was clear that Miss Pike was still breathing".

Reporters heard gasps and complaints

Reporters who witnessed the attempted execution described gasps and complaints from Pike about pain, according to Sky's US partner network NBC News. They said she was kicking her feet so much that she knocked off the sheets laid on her.

At 7.27pm local time, moments before the first lethal injection was administered, Pike described herself as being at peace, and said: "I'm going to leave this world the way I spent most of my life, and that is in love."

But she remained awake, and by 8.26pm, the second dose of pentobarbital had been administered.

Execution witnesses described hearing her snoring behind a closed curtain until the microphone was turned off at 8.53pm, and everyone was asked to leave.

'One of the worst botched executions'

The state's execution protocol calls for a second dose to be administered "if the inmate is not deceased" after the first. It does not spell out what happens if the subject is still alive after that.

"This is one of the worst botched executions in the modern death penalty era," the Death Penalty Information Center (DPI) said in a statement.

"Christa Pike's attorneys specifically warned Tennessee officials of the dangers, but they were ignored. This debacle was entirely preventable."

The DPI - a non-profit organisation - does not take a position on the death penalty itself, but is critical of problems in its application.

Tennessee Governor Bill Lee said he had ordered "a comprehensive, third-party review to determine exactly what occurred", and suspended all remaining scheduled executions this year.

Victim's mother outraged

Pike and her boyfriend, Tadaryl Shipp, were convicted of torturing and killing Colleen Slemmer, a 19-year-old classmate of theirs, at a job training facility in the city of Knoxville in 1995.

Prosecutors said Pike, who was 18 at the time, feared she was trying to steal her boyfriend, and lured her to a wooded area.

A pentagram, a star-shaped symbol associated with Satanism, was carved on the victim's body, which, along with other elements of the crime, stoked fears of Satan worship during the so-called "satanic panic" in the country during the 1980s and 1990s.

Shipp, who was 17 when the crime was committed, received a life sentence with the possibility of ​parole.

Pike does not deny the killing, but her supporters have argued the state should consider her age at the time, mental illness and a history of severe sexual abuse, including rape, beginning when she was a child.

'They f***ed up'

May Martinez, who had travelled to Nashville to witness the execution of her daughter's killer, described the attempt as "a mess" in a phone interview with NBC News on Thursday morning.

"They went to try to execute her, and she didn't die," she said.

She said Pike never expressed remorse during the attempted execution.

"Not nothing...about what happened, you know, to Colleen," she said.

She criticised the communication about what was going on from officials.

"We didn't know anything until we got up to the office and saw the commissioner," she said. "And he said that it didn't work, that it didn't work, and she's on her way to the hospital."

Asked what her message to the governor and attorney general was, she replied: "They f***ed up."

'Singular and unparalleled'

On Wednesday, a federal appeals court halted Pike's initial execution after ordering a review of whether her allegations of childhood sexual abuse and rape were fully considered when she was sentenced to death by a judge in 1996.

The US Supreme Court had earlier this week rejected a bid by Pike's lawyers to halt her execution, after Mr Lee had denied her petition for clemency.

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Pike is the only woman on death row in Tennessee. The last execution of a woman in the southern state was in 1820, historical records show.

Seven other people have survived medical problems due to the execution team's failure to access a vein to administer lethal injection drugs, but no one has stayed alive after receiving the drugs used in such executions, according to Robin Maher, executive director of the DPI.

Ms Maher said what Pike experienced was "singular and unparalleled".

It is the second failed execution in Tennessee this year.

In May, the execution of Tony Carruthers, convicted of killing three people in 1994, was called off after officials could not find a suitable vein for his lethal injection.

Last October, the lawyer of convicted child killer Byron Black claimed that he showed signs of "sustained cardiac activity" two minutes after he was pronounced dead following his execution in the state.

Concerns had been raised that Black was being put to death with a working defibrillator implanted in his chest.

Some of the worst unrest was in the southern city of Marseille, France's second-largest, where protesters started fires in at least two high schools, officials said.

Two teachers were accidentally splashed with petrol at the city's Victor Hugo high school, while at the nearby Saint-Exupery high school, hundreds of young people forced firefighters to leave their truck before setting it alight.

Marseille's public transport system was suspended after staff were injured in the clashes.

The Nelson Mandela high school in the western city of Nantes was evacuated after it was set alight, according to mayor's deputy, Olivier Chateau, who told broadcaster franceinfo that the fire was under control and ⁠there had been no injuries.

The facade of a school in Le Havre in the north suffered fire damage, at least one car was torched in the northeastern city of Strasbourg and riot police clashed ‌with youths in Toulouse in the southwest.

In the Parisian ⁠suburb of Saint-Denis, crowds of young people massed in front of a line of police. One student held up
a ​sign that read: "Can we explain ourselves without being teargassed?"

Hundreds of people have been arrested and dozens injured during the protests, which began as a series of demonstrations and blockades around the capital last month.

Thursday's clashes followed a series of deeply unpopular spending ⁠cuts announced by ministers in the 2027 budget earlier in the day.

France's intelligence agencies told ministers on Thursday that hard-left politicians initiated the campaign, according to a source close to the prime minister quoted by Reuters.

The unnamed source said officials pointed to "LFI [France Unbowed] and its proxies on the far left".

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LFI MP Louis Boyard dismissed the accusation, telling BFM TV the group "has always advocated non-violent demonstrations".

Ministers turned it into a political battle "by insulting and repressing high school students", he said.

Prime Minister Sebastien Lecornu held a crisis meeting on Thursday afternoon while French education minister Edouard Geffray ​said he would meet unions, parent associations and ⁠student groups on Friday.

Students have accused the police of using heavy-handed tactics, including the use of tear gas.

The government criticised the violence that ⁠broke out during some of the protests, but said difficulties in ​high schools should be acknowledged and addressed.

Retired plumber John Burke, 86, was assaulted in the home he shared with his wife Peggy during a burglary in east London early on 29 September last year.

He was taken to hospital, and discharged a few hours later, but died at home the next day.

Ashley Malcolm, of Hackney, had headbutted him when he was challenged during the break in.

He admitted burgling Mr Burke's home, along with another burglary, an attempted burglary and possession of cocaine.

He denied murder but pleaded guilty to the lesser offence of manslaughter part-way through his trial.

In a televised sentencing at the Old Bailey on Thursday, Judge Simon Mayo KC said Malcolm broke into the home of "two elderly and vulnerable" people and the burglary took place over a "prolonged period".

"During the course of that burglary you headbutted Mr Burke. That headbutt fractured his nose and caused intercranial bleeding, and he died as a consequence."

Grandson Reece Lambert said he believed his grandfather was attacked as he "protected the woman he loved with everything he had left".

Family's 'immeasurable' loss

Judge Mayo acknowledged the "immeasurable" loss felt by Mr Burke's family, including his widow with whom he had been married for many decades.

He told Malcolm, who has 12 more convictions for burglary and attempted burglary over 20 years: "You're now 40 years of age. You have an extensive record of previous offending, both as a youth and an adult, extending over 25 years."

Handing him a 23-year sentence made up of 18 years in jail and five on extended licence, Mr Mayo said he had "decided to reflect all your offending in the sentence I impose for the manslaughter of John Burke".

Within hours of burgling the elderly couple, Malcolm broke into a care home and attempted to burgle another flat while the occupants were at home.

The court heard that doctors at the nearby Homerton Hospital had failed to spot that he had bleeding on the brain and a broken nose when they discharged him after carrying out tests.

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The following morning, his son Sean found him unconscious on the floor of his bedroom, and further tests at the hospital confirmed he had sustained a "devastating and irreversible" brain injury from which he died, as well as multiple areas of bruising and a broken nose.

A 'quiet, hard-working' man

Sean Burke said his father "did not deserve to die in such a way", describing him as a "quiet, hard-working, easy-going man who never had a bad word for anyone.

"He was the man that showed me that hard work, respect, good manners and a good heart would always pay off."

He said there was "nothing of any value in the house as my parents did not have much but they had each other".

Defence barrister, mitigating, Emin Kandola referred to a statement in which Malcolm wrote: "I'm very sorry about what happened. It was an accident. I'm very sorry to the family."

The country's number of brown bears has more than doubled in the last 30 years to 308,000, partly due to shorter, milder winters.

As a result, Moscow said it would consider lifting hunting quotas on brown bears, as well as establishing regional population limits, giving local authorities extra powers to control their numbers, and identifying regions that need more financing to tackle the problem.

It follows a spate of attacks, with a woman in Siberia - home to nearly 27,000 bears - mauled to death by a bear in her garden last week.

Investigators in the city of Krasnoyarsk also said last week that they had opened a criminal case into the local environment ministry, accusing it of negligence that led to the deaths of seven people in September.

In one of the most high-profile attacks this year, a bear attacked two tourists in their tent in the Altai region in August.

It dragged one of the tourists, a 29-year-old woman, out of the tent, killed her, and then buried her in the forest.

And in the Siberian region of Tuva, ice hockey coach Alexander Kuzmenko - father of NHL player Andrei Kuzmenko - was killed by a bear while on a fishing trip last month.

"It is clear that as the population grows, so too does the number of problems," deputy prime minister Dmitry Patrushev said.

"Systemic measures are needed to ensure that humans and animals can coexist safely and to maintain the necessary balance."

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Russia's environment ministry has sought to play down the spate of attacks, telling the RBC news outlet: "In recent years, around 20 to 30 cases of bear attacks have been recorded annually.

"The only abnormal spike was in 2014, when there were 166 cases. The thing is, nowadays everyone has a smartphone, and information spreads quickly via the internet and social media, which creates the impression that the problem is widespread."