A teenager has been arrested in connection with a knife attack that left one teenager dead and another critically injured.
The 13-year-old boy was arrested in his home in Leytonstone, north-east London at 12.40am on Saturday, and is now in custody at a north London police station.
A 14-year-old was killed in the attack on Friday night, becoming the sixth teenager to die in a knife attack in just a month.
Police said the two victims were friends and the 15-year-old remained in hospital.
The pair were attacked by a gang of youths in the entrance of the Leytonstone tower block shortly before 8pm yesterday. Police said a gang of youths was seen running from the scene shortly afterwards.
The injured teenagers staggered 200 yards on to a busy street and were discovered by officers called by a passing pedestrian. Police have not named the teenagers but said both victims were black and lived in the Leytonstone area.
Det Chief Insp Matthew Horne said: "We understand a large group of youths were involved in an incident in the foyer of Gean Court, a block of flats in Langthorne Rd E11, during which we believe the two victims were stabbed.
"It is believed they then managed to stagger the short distance to nearby Crownfield Road.
"A number of youths were seen running from the scene.
"We are appealing for anyone who was present during the incident to come forward, along with any witnesses or anyone with information on this appalling crime."