A good Samaritan today told how 25 teenagers threatened to stab him as he saved a cyclist from losing his bike in a gang mugging.

Lee Anderson, 44, intervened with his partner Steve when they spotted the cyclist being ordered to hand over his bike by about 25 youths - including three in school uniform - in Broadway market, Hackney.

The confrontation - part of which was caught on camera by a neighbour - lasted about 15 minutes around 8.30pm on Wednesday before the gang ran off to a nearby estate.

Mr Anderson, who works for the charity Kids Company, said police initially told him there was nothing they could do because the incident happened on the gang’s “turf”. The attackers are believed to belong to the LFC (London Fields Crew).

However after news of the incident began to circulate on social media yesterday, an officer told him that it was now being investigated - even though the cyclist does not want to press charges - because of the threat of knife violence.

Mr Anderson, who was hospitalised last year after trying to prevent youths spraying graffiti in the area, told the Standard: “They said they were going to stab us. The video doesn’t really capture the full extent of it.

“We got his bike back for him. He was really, really pleased. He came over and cuddled us and asked if he could buy us a drink, but we wanted to get home quickly.

“If you see someone being robbed and stand back and do nothing, you just become part of it.”

Last year Mr Anderson was sprayed in the face with paint, was cut with keys being thrust into his neck and had his voicebox stamped on after telling youths to stop spraying graffiti in Broadway market.

“The police need to start answering questions about what is being done about gang culture in this area,” he said.

“There are so many areas across London where it seems they can get away with stuff. I would like to know why they can’t be prosecuted. They are lawless. We have got kids running around, running whole areas.

“My mum keeps saying ‘don’t get involved’ but I can’t stand by. If you start letting them get away with it, they become less and less frightened of you. I want them to be frightened of the community, and for us to say: ‘We are not going to put up with it.’ Too many people in this country don’t stand up for each other.

“I said to a couple of the boys: ‘Walk away from these gangs you are in.’ I feel sorry for these kids.”

The Met police said that police were called to Duncan Road, Hackney, after a 44-year-old man reported the theft of his bicycle.

A police statement said: “The man left his bike unattended by railings near Broadway market. A few minutes later he saw another man riding his bike nearby. He challenged the man and recovered his bike. At this point members of the public intervened and an alteration ensued.”

There have been no arrests but inquiries continue. Anyone with information is asked to call the police on 101.