Stephen Lewis was stabbed twice, once in the heart
A teenager has been found guilty of stabbing a 15-year-old boy to death outside a church hall in east London.
Stephen Lewis was knifed in the chest in Plaistow, east London, in January. He died later in hospital.
A 17-year-old youth was found guilty of his murder and Rissasy Nyimbi, 18, from Victoria Docks, east London, was found guilty of manslaughter.
The Old Bailey heard that police faced a wall of silence as youths at the scene denied seeing anything.
Hundreds had attended a "back-to-school"-themed youth event at the church in January, which ended early when gatecrashers arrived, the court heard.
During a subsequent row Stephen was surrounded by a group of youths, some of them shouting, "shank him", meaning "stab him". He was stabbed twice, once in the heart.
An anti-knife crime patrol that happened to be in the area was at the scene within seconds, the Old Bailey heard.
They found knives scattered over the floor but youths who were there told officers: "We didn't see anything," and said: "I had my eyes closed."
Prosecuting, Richard Whittam QC said: "For whatever reason, there was a clear reluctance of some of those present to help the police."
A 16-year-old youth who was persuaded to give evidence named Stephen's killers in court.
Mr Whittam said the murder was not part of an "organised attack between rival gang members" but may have been caused by "an element of adolescent identification with particular groups or areas".
Nyimbi and the 17-year-old, who cannot be named for legal reasons, were remanded in custody to be sentenced on 13 November.
A third youth, aged 16, was cleared earlier in the trial due to lack of evidence.