Eye witness describes scenes as man 'waving large knife'
A witness told Sky News of scenes aboard the train, and of a person "waving a knife".
His full statement reads: "What happened was I was in coach G, and there was quite a few people coming through coach G, andone of the people that were coming through... I heard them say..'I've been stabbed'...
"So they were making their way through the carriage to get away from the incident, from the suspect.
"They were extremely bloodied. That person ended up when we pulled in, they were basically on the floor.
"We couldn't progress further down the train away from the suspect, because that person ended up collapsing on the floor."
"We were ushered out of the station on the platform, and there was multiple people that had been stabbed that were making their way down, but the suspect had also come off the train as well.
"So while we were being told to come out of the station, the suspect was obviously running around them as well, and I don't know the reason. No one knows the reason why."
He added: "The armed police were pointing to the suspect as we come off the train, I asked what that suspect looked like. They said, it's a Black male in all black, so a black hoody.
"And then at the back of the station, walking calmly as the police were coming through, the armed police, I said, I think that's the guy.
"And essentially, as they got closer to him, they started shouting, to get down, get down. He then was waving a knife, quite a large knife, and then they detained him.
"I think it a taser that got him down in the end, but I only saw one person at that point.
"I did not see anyone get stabbed, but there was a lot of people being moved away from being treated for injuries and coming away with colleagues.
"I'd say probably maybe 12 people."