London's murder rate is soaring because "feral" youths are stabbing people multiple times with zombie knives, making it virtually impossible for paramedics to save them, one of Scotland Yard's most senior officers has suggested.
Metropolitan Police Assistant Commissioner, Martin Hewitt, said the level of violence had got significantly worse over the past five years with his officers now routinely administering "trauma medicine" on the streets of the capital.
His comments came as a 20-year-old man was found fatally stabbed in north London after reports of a fight on Wednesday evening.
The Metropolitan Police said officers were called shortly after 6.30pm to reports of a brawl between men armed with baseball bats in Cavendish Road, Edmonton. The victim had stab wounds and was pronounced dead at the scene.
A 16-year-old boy was later arrested on suspicion of murder and was in hospital for treatment before being taken to a north London police station for questioning, officers said.
Speaking at a knife crime summit, organised by the Mayor of London, Mr Hewitt said the trend towards using so-called zombie knives was making medics' jobs even more difficult because of the seriousness of the wounds being inflicted.
He said: "The violence is getting greater. If I was stood here five years ago, I would probably be talking about knife offences where there was generally a single puncture wound.
"We are now routinely seeing multiple stabbings. That is one individual stabbing somebody multiple times.
"And increasingly seeing group offending as well. By that I don't mean there's a group and one person is stabbing, I mean there's a group of people who are all using weapons.
"Some of the CCTV footage that we see is shocking and quite frankly feral when you look at a group of individuals bearing down on another person."
Mr Hewitt added: "You will have all spotted the other trend change which is the nature of the weapons being used. These so called zombie knives, the hunting knives and machetes.
"We have all seen the imagery which quite frankly is shocking and horrific from the perspective of how people view London."
There have been more than 80 murders in the capital this year with more than half of them involving knives. If the current trend continues 2018 could be London's bloodiest year for more than a decade.
Met Police Assistant Commissioner Martin Hewitt
But highlighting the murder of 15-year-old Jordan Douherty, who was stabbed to death in Romford, east London, on Saturday night, Mr Hewitt said the police were often met with a wall of silence when investigating the crimes.
He said: "The murder that took place over the weekend in Romford was outside a party where there were very many numbers of people none of whom saw anything that they were prepared to talk to the police about."
Mr Hewitt said while knife crime had increased across the country, it was the nature of the attacks in the capital that was driving the murder rate up.
He explained: "Every single time anybody uses a knife against another person that is potentially a murder. The reason it doesn't become a murder is often luck in terms of where the wound goes in and sometimes by the intervention that my officers are doing on the street.
"I have large numbers of officers now all over London who are routinely administering what you would call trauma medicine on the pavement and on the street in London to people who have been stabbed. And then the work obviously of paramedics and the doctors and everybody else that comes in.
"But the more violent the offences, the more chance there is that somebody is going to receive a fatal wound and I think that is part of why we have ended up where we are with the murder rate."
Mr Hewitt said while the rise in violence could not be attributed to any one reason and affected communities of all ethnic and socio-economic backgrounds.
He said while the police had a “fundamental and critical role” to play, in tackling violence, other agencies had to play their part in addressing the causes of crime.