Police said they were called at 7.39pm on Saturday (6.39am Sunday AEDT) after reports that “multiple people” had been stabbed as the train from Doncaster to King’s Cross headed south towards Huntingdon, about 120 kilometres north of London.
“Nine are believed to have suffered life-threatening injuries. A major incident has been declared and @TerrorismPolice are supporting our investigation,” the service said in a statement on X.
British Transport Police Chief Superintendent Chris Casey described the attack as shocking.
“We’re conducting urgent inquiries to establish what has happened, and it could take some time before we are in a position to confirm anything further,” he said.
Paul Bristow, the mayor of Cambridgeshire and Peterborough, said he had heard of “horrendous scenes” during the attack, which began shortly after the train left Peterborough station. Passengers pulled the emergency alarm to alert the driver to the danger.
One witness described wounded passengers running through the carriages to escape the attack.
“They’ve got a knife, I’ve been stabbed,” one of the victims told other passengers during the mayhem, according to one witness who described the events to Sky News UK. This victim collapsed on the floor and was taken to an ambulance once the train came to a stop.
The witness described the victim as “extremely bloodied” from the knife attack. No explanation was given for the attack in any of the accounts in the immediate aftermath of the events.

Emergency personnel inspect the train at the Huntingdon following the attack.Credit: AP
“There were multiple people that had been stabbed who were making their way down [onto the station], but the suspect had also come off the train as well,” the witness said.
He added that he did not witness the attacks but saw some of the victims.
“The armed police were pointing to the suspect as he came off the train,” he said, adding that he was told the suspect was a male dressed “in all black” who was “waving a large knife” before being taken down.
The second suspect was then halted by police with what appeared to be a Taser, he said.

Emergency personnel on the tracks at Huntingdon train station in Cambridgeshire after the stabbing attack.Credit: AP
A second witness, Oliver Foster, also described passengers rushing through the train to escape the attackers.
“There was a girl, bless her, who was really, really in a bit of a state,” Foster told the BBC. “Because the guy had actually tried to stab her, and one of the older guys, who was an absolute hero, blocked it with his head. He had this gash on his neck, and we’ve given him, like, a jacket to keep the pressure on.”
The passengers could not barricade the doors and waited in their carriage without knowing whether the attackers would make their way through the train.
“It felt like literally forever and then the train came to a stop,” Foster said.
Passengers escaped onto the platform at Huntingdon while police and emergency services swarmed onto the station.
A third witness described the scene on the train as “horrific” and “pure chaos”.
“There was blood everywhere,” the witness told The Sun.
“It was a terrible scene, really violent. It was like something from a film. It didn’t feel real and just sparked pure panic on board.”
British Prime Minister Keir Starmer expressed concern about the “appalling” events.
“My thoughts are with all those affected, and my thanks go to the emergency services for their response,” he said.

Emergency vehicles line up at the scene.Credit: Getty Images
Home Secretary Shabana Mahmood confirmed the arrests and cautioned against conjecture.
“Two suspects have been immediately arrested and taken into custody,” she said. “I am receiving regular updates on the investigation. I urge people to avoid comment and speculation at this early stage.”
The attack caused widespread disruption, halting transport on the busy rail lines on Saturday night.
Conservative Party leader Kemi Badenoch said she was deeply disturbed by the reports from Huntingdon.
“This is an absolutely horrific attack and my thoughts are with all those affected, including the emergency responders at the scene,” she said.
With Reuters, AP
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