David Pethers, 33, was attacked last Saturday at Leytonstone Underground station by a knife wielding man, who shouted ‘This is for Syria’.
He attempted to grapple and restrain the man even when he had been slashed in the neck.
Mr. Pethers said that other commuters filmed with their phones and spectated while he and another person tackled the attacker.
Speaking to the Daily Mail, he said: ‘There were other adult men standing there, just filming it on their phones. There were so many opportunities where someone could have grabbed him.’
He said: ‘I was walking down into the station … as I got to the ticket office there was a pool of blood on the floor and a guy with a knife going mad.
‘Basically, the scene I walked into was the guy lying on the floor, blood everywhere, and this guy shouting and that is when I tried to get everyone out of the station.
‘There was a guy with a rucksack saying “Calm down, let’s talk about this” and I saw this guy was going to go for him.
‘Basically, we kind of contained him in the main ticket area. He kind of went for me and I went for him and he cut my neck.
‘I was dragged away, I was bleeding from the neck. I know it sounds crazy but I went back to have another go.
‘Then the police turned up. They fired four Tasers and then they contained the situation from there.’