A teenage boy became the 11th person to die from knife crime in London in a fortnight when he was stabbed by two men who may have fled on bicycles.
The 17-year-old victim, named locally as Elijah Dornelly, was ambushed as he walked with a friend in the centre of Walthamstow, northeast London, on Sunday night.
According to figures from Scotland Yard, the unnamed 17-year-old was the ninth teenager to be murdered in the capital this year, with six of those incidents involving knives.
Police have launched a murder investigation and urged witnesses to come forward.
Officers were called to the High Street just after 11.30pm and found the male suffering from a serious stab injury. He was taken to a hospital in east London and died a short while later.
Detective Chief Superintendent Michael Gallagher, the Met's "Silver lead" for knife crime, said: 'This operation carries a positive and powerful message: this is about all of us addressing a problem that often has tragic consequences. "At this stage we are investigating whether the two suspects left the area on bicycles".
The force said it is tackling knife crime under its Operation Sceptre, which saw 73 arrests made for possession of an offensive weapon or knife during the past week.
The victim, from Hayes, west London, was taken to a hospital in west London but died shortly after. Siddon was stabbed to death during a fight outside a barber's shop in Harlesden Street.
Officers seized 300 knives, along with 62 offensive weapons and 15 firearms over the period.
Anyone with information is asked to contact police on 101 or call Crimestoppers, anonymously, on 0800 555 111.