Three American men are being hailed as heroes for overpowering a heavily-armed gunman on a train in northern France.
The incident happened on the high-speed Thalys service near Arras. A 26-year-old Moroccan man was arrested at Arras station.
One of the Americans said they took an AK-47 assault rifle and a handgun from the attacker as they saw him walk down the aisle of the train.
They then put him in a chokehold until he was unconscious.
Two of the American men who overpowered the gunman, Spencer Stone and Alek Skarlatos, are members of the Air Force and the National Guard respectively.
They were travelling on the train from Amsterdam to Paris on Friday evening with a childhood friend, Anthony Sadler, who also helped restrain the attacker.
“Spencer got to the guy first and grabbed the guy by the neck,” Mr Skarlatos told Sky News.
“I grabbed the handgun, got that away from the guy and threw it. Then I grabbed the AK-47, which was at his feet, and started muzzle-bumping him in the head with it.
“Everybody just started beating the guy while Spencer held the chokehold until he went unconscious.”
When he checked the AK-47, Mr Skarlotos said it had jammed and would not have been able to fire. The cartridge for the handgun had also been dropped, he said.
French authorities said three people were injured, two of them seriously – one with a gunshot wound, the other a knife wound.
Chris Norman, a British man living in France, was also hurt while trying to subdue the attacker.
“I came in at the end of it all and helped get him under control,” he said at a news conference in Arras.
“The guy pulled out a cutter and started cutting Spencer – he cut behind his neck and nearly cut his thumb off.”
Another man, who has not been identified, suffered severe cuts to his neck. Spencer Stone went to help him despite his own injuries. Mr Stone remains in hospital.
“I’m really proud of my friend that he just reacted so quickly and so bravely,” Anthony Sadler said.
“He was really the first one over there. Even after being injured himself, he went to go help the other man who was bleeding also. Without his help, he would have died.
“That man was bleeding from his neck profusely.”
Social worker Christina Coons from New York was one of the 554 people on board. She told BBC Radio 5 Live she ducked under her seat when she heard shots.
She said: “None of these men were in uniform. They were just regular passengers, this afternoon, who stepped up to the plate as soon as they saw what was happening.”
The passengers included French actor Jean-Hugues Anglade, the star of Betty Blue and Nikita, who was lightly wounded breaking glass to sound the alarm.
The American men and Mr Norman were awarded medals for bravery by authorities in Arras.
US President Barack Obama was among those to praise those who took action.
“The president expressed his profound gratitude for the courage and quick thinking of several passengers, including US service members, who selflessly subdued the attacker,” the White House said in a statement.
“It is clear that their heroic actions may have prevented a far worse tragedy.”
French Interior Minister Bernard Cazeneuve said the passengers were “particularly courageous and showed great bravery in very difficult circumstances”, adding: “Without their composure we could have been confronted with a terrible incident.”
Belgian Prime Minister Charles Michel called the incident a “terrorist attack”.
French media said the arrested man was known to the intelligence services but he has so far refused to talk to police in Arras.
AFP and El Pais newspaper said he used to live in Spain until last year, when he moved to France. They reported that he was known to intelligence agencies.
He is now being questioned by anti-terror investigators in Paris.
Images shared on social media appeared to show him being restrained on the station platform in Arras.
France has been on edge since the attack on the Charlie Hebdo magazine and a Jewish supermarket in Paris in January, which left 17 people dead.
And in June a man said to be inspired by the Islamic State group beheaded his boss and tried to blow up a gas plant in southern France.
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