Image copyright Gemaros Michalopoulos Image caption Gemaros Michalopoulos broadcast the footage of the incident via Facebook Live
A passenger who posted a video on Facebook showing passengers fleeing as a man allegedly held a knife to his throat has said he thought he would be killed.
Gemaros Michalopoulos said his train was stuttering as it pulled into London Waterloo on Tuesday.
When it stopped, a man with a knife was seen jumping on the train and then attacking passengers.
Mr Michalopoulos, who is now temporarily unable to use his legs, said: “I thought I would be the one to be killed.”
He described the chaos of the scene to British Transport Police (BTP) as police managed to subdue the attacker.
The suspect, believed to be a 40-year-old south London man, was taken to hospital with a suspected knife wound to his leg.
Police are appealing for information from other train passengers and off-duty police officers.
“For the accused to strike this woman and her young son with what he thought was a toy handgun, close enough for her son to understand the threat, is inhumane,” said Deputy Chief Constable Steve Spence, the BTP’s Head of Operations.