A passenger on a train where a mass stabbing took place said he initially thought it might have been a suicide bomber, a court has heard.
Milan Campion was travelling on a London-bound LNER service on 1 November last year when it made an unscheduled stop at Huntingdon amid an attack by Anthony Williams, Cambridge Crown Court heard.
Campion told jurors Williams was "threatening everyone indiscriminately" so he "came to the conclusion that he wasn't sound of mind".
Williams, 33, of Peterborough, denies 10 counts of attempted murder on the train. He is also charged with four other attempted murders following earlier incidents in Peterborough and London.
In a video interview played to jurors on Monday, Campion said he got on the train at Grantham, adding "quite a lot of us had travelled from the Nottingham Forest versus Manchester United game".
The court heard how Campion, who is not one of those Williams is accused of trying to kill, opened a toilet door to find Williams inside.
Campion said "he was just sitting on it staring at the ground" and it was "weird that he hadn't locked the door".
He said later he heard people shout "there's a guy with a knife" and there was a "big chain of us running down the aisle shouting to follow us".
"I thought it was a bomb at first," he said.
"I thought it might have been a suicide bomber so I need to get as far away as possible to maximise your chance of survival if it goes off."
Campion told jurors he spoke to Williams in the catering section of the train.
He said he told the attacker "you can't win - what you trying to do?" and "it's not worth it".
He said Williams was "remonstrating with no-one in particular" and was shouting something but he "couldn't tell you what he was shouting".
"He just looked angry, you could see the anger in his eyes," the witness said.
The trial also heard from witness Dinaria Soares who was sat across from footballer Jonathan Gjoshe, who jurors have heard was the first person attacked by Williams on the train.
She said she saw the knifeman "hit him on the shoulder... I was surprised and confused at first".
Then when the attacker pulled his arm back she saw a knife, before describing a "stabbing motion had a lot of force behind it".
The court heard she went to the front of the train where people were "trapped like sardines as there was nowhere else to move".
During the prosecution opening, jurors were told Williams "has some mental health issues which may or may not become relevant during this trial".
As well as arguing Williams was attempting to murder the 10 people on the train, prosecutors allege that on 31 October he tried to kill three people in Peterborough.
He is also charged with attempting to murder a teenager in the early hours of 1 November on a DLR train in east London.
Whether Williams carried out the attacks is not in question - the court has been told - but jurors must consider whether he intended to kill.
The trial continues.
