A teenager was stabbed to death following a fight between a group of youths, police said today.
Police were called to reports of a fight involving a group of male youths in Black Prince Road, Lambeth, south London, just after 11pm last night.
By the time officers arrived, the group had dispersed.
A few minutes later, at 11.15pm, a 15-year-old was brought into nearby St Thomas' Hospital suffering stab wounds.
Police believe he was driven there by a member of the public.
He was pronounced dead shortly after midnight.
Officers from Scotland Yard's Specialist Crime Directorate are investigating the attack.
They believe they know the victim's identity, but still await formal identification. He is black and from the local area.
The attack is another in the list of recent stabbings which have highlighted the issue of knife crime and Britain's worsening knife-carrying culture.
The victim was stabbed once in the left side of his chest.
Scotland Yard said the teenager was thought to be with a group of friends who got off a bus in Kennington Road.
They were met by a second group of youths who goaded them into Black Prince Road and a row broke out, leading to the fatal stabbing.
Detectives are examining CCTV footage while carrying out an extensive search of the area.
The suspects are believed to be a group of around 10 black men in their late teens and wearing dark clothing.
Detective Superintendent Richard Heselden, from the Specialist Crime Directorate Homicide Investigation, said there must have been a considerable number of witnesses.
"We would appeal to anyone who was in the area at the time to come forward and tell police what you saw," he said.
"It was a warm summer evening and we are sure the streets would have been busy at the time of the murder."
A post mortem examination is due to take place at Greenwich mortuary tomorrow morning.
The police spokesman said an inquest would be opened and adjourned at Southwark Coroner's Court "in due course".