A 22-year-old woman has been arrested on suspicion of murder in connection with the fatal stabbing of a teenage boy in a fight in east London.
Joel Adesina, who was 15 and from Dagenham, was found stabbed in the abdomen on Bethnal Green Road, Tower Hamlets, at 23:00 GMT on Friday.
He was taken to hospital but died at 02:12 the following day.
An 18-year-old man arrested at the scene has been released with no further action to be taken, police said.
Detectives are keen to speak to anyone who may have witnessed an altercation in Padbury Court, just before the stabbing, between a group of male youths on foot and the occupants of a car.
The dispute carried on to nearby Gibraltar Walk.
Joel was part of the group on foot, police said.
A post-mortem examination will be held in due course.
Det Ch Insp Chris Jones said: "Anyone who may have witnessed this altercation or have information which could assist the investigation is asked to contact the police as soon as possible."