Teachers are patrolling the streets and getting on buses to accompany children home, in a bid to combat knife crime.

Pupils making their way to and from school can become targets for gangs and drug dealers so need extra protection at these hours, the head of one of London’s biggest academy chains has said.

Sir Dan Moynihan, chief executive of the Harris Federation, a multi-academy trust that runs 46 schools in and around London, said: “You tend to get youths and other individuals coming to schools at the end of the day with various intentions and that can create flashpoint.

“In the past it was always the time children were most likely to be mugged or get into disputes. Now obviously there is a new twist, as it is also a peak time for stabbings.”

This week, Ayub Hassan,a 17-year-old boy who dreamed of becoming a barrister, was stabbed to death in west London. His death death was the fourth fatal stabbing in a week across the country and has led to a major debate between the Government and police about how best to tackle the crisis.