Two teenage boys have been killed in separate stabbings amid concerns about a surge in violence over the summer.
A 15-year-old died in Woolwich, south-east London, and a 16-year-old in Lambeth, south London, on Monday.
Police have been gearing up for an increase in violence during the summer months after a surge last year when lockdown measures were eased.
In April, officers staged a national crackdown on knife crime, Operation Sceptre, which included deploying knife arches and sniffer dogs as well as encouraging the public to hand in weapons.
At the time, Metropolitan Police Commander Alex Murray told the PA news agency: “We fully expect, as people come back on to the street, and with summer approaching, that people might be tempted to engage in violence, or the ingredients might be there.
“We’ve been spending a lot of the lockdown period preparing and getting ready to suppress as much violence as possible.”
The force said the 15-year-old boy died after being stabbed in Woolwich New Road in Woolwich, south-east London, shortly after 5.20pm.
Violence erupted in a busy area near Woolwich Arsenal station and pictures on social media showed members of the public holding up sheets to provide privacy as emergency crews tried to save the boy’s life.
Another 15-year-old, who later took himself to hospital suffering from a knife wound, has been arrested on suspicion of the other boy’s murder.
In Lambeth, a 16-year-old boy was pronounced dead at the scene after being found injured in Oval Place. There have been no arrests.
The family of both boys have been told.
Superintendent Petra Lazar said of the Greenwich incident: “It is shocking and extremely saddening that a teenage boy has lost his life as the result of knife crime.
“My thoughts at this time are with the family of the boy who has died.
“This incident will understandably cause worry and concern to local residents and I would like to reassure them my officers are supporting the murder detectives in every way we can.
“Increased patrols will be carried out in the area over the next few days.”