One man is dead and another is fighting for life in hospital after a double stabbing near Regent’s Park.
Footage shows officers performing CPR on one of the victims in the front garden of a flat in Lilestone Street in Westminster about 3.20pm on Monday.
A Met spokesman said one man, believed to be in his 20s, was pronounced dead at the scene. It is the fourth killing in London in three days.
In a statement Scotland Yard added enquiries are ongoing to identify and inform his next of kin.
The second man was taken to hospital where he remains in a critical condition.
DCS Owain Richards, the local policing commander for Westminster, said: “This is a tragic incident and I am deeply saddened that another young life has been lost to knife crime on the streets of London.
“I know the community will join me in sending our thoughts to the victim’s family at this awful time.
“I appreciate people will want answers about what happened, but I would like to ask that our dedicated team of detectives are given the time and space they need to conduct their enquiries. A large number of officers will remain in the area and I’d encourage anyone with immediate concerns to speak to them.”
No arrests have been made.
It came after Charlie Bartolo and Kearne Solanke, both 16, were stabbed to death in separate locations around a mile apart in Greenwich just after 5pm on Saturday.
A 16-year-old boy has been arrested on suspicion of the murder.