Flowers and tributes have been laid at the spot where a 15-year-old boy was stabbed to death on Loughborough Estate, Brixton.
Police were called to a disturbance outside Secker House at about 9.30pm last night. They found the victim, named locally as Junior, with fatal knife injuries.
A 14-year-old girl has been arrested and remains in custody in relation to the incident.
Police believe they know the identity of the young man, and have informed his family, though they await formal identification.
Officers have opened a murder investigation and this afternoon appealed for information. They do not believe the incident to be gang related.
Detective Chief Inspector Charles King, leading the probe, said: “We would appeal for anyone who has any information or witnesses to come forward as soon as possible.”
Anyone that may assist the inquiry should call detectives on 020 8721 4054 or Crimestoppers anonymously on 0800 555 111.