Metropolitan Police commissioner Cressida Dick said the last few years “undoubtedly have been the highest and most worrying levels in my service”.

She added: “If you look at stabbings of young people I do think this is a new and tragic and worrying phenomenon.”

Earlier on Tuesday, another teenager received multiple stab wounds in south-east London.

A male, believed to be aged 18, was taken to hospital with injuries not thought to be life-threatening after the incident in Thyme Close, Blackheath, at around 3.24pm.

And a 17-year-old boy was stabbed in Waterside Close, Barking, east London just before 7pm.

He was taken to hospital with injuries not thought to be life-threatening, police said.

An 18-year-old man was stabbed in Tooting High Street, south-west London, just after 9pm.

He was taken to hospital and his condition is not yet known.

Anyone with information should call police on 101.