4 July 2011 Last updated at 15:21 ET

Boys sought in Yemurai Kanyangarara murder in Welling

Yemurai Kanyangarara (pictured with his mother) was murdered on Friday

Officers investigating the murder of a 16-year-old in south-east London have urged three boys to give themselves up.

Yemurai Kanyangarara, from Belvedere, died after being stabbed in the neck as he got off the number 96 bus in Upper Wickham Lane in Welling on Friday.

The pupil of St Columba's Catholic Boys' School had moved to Leicester to avoid violence, his friends said.

The Met said "three frightened teenage boys", aged about 15, were on the run or hiding in the Greater London area.

The victim, who had just finished his GCSEs, came to the UK from Zimbabwe as a toddler.

He had been living with his father in Leicester and had come to London only to sit his exams in the school in Bexleyheath.

Suspects 'in hiding'

He was with a friend at the time of the attack.

Det Ch Insp Mark Dunne said: "We currently have three frightened teenage boys who we know have left home and are on the run from police, possibly hiding in the Greater London area.

"This cannot go on forever and sooner or later they will have to speak to me.

"I am appealing for them to come forward now for the sake of Yemurai's family, who needless to say are absolutely devastated by his death."

He also urged witnesses to the incident, which happened outside the Superdrug store, to come forward.

Police believe three teenagers from another school, who got off an earlier 96 bus, approached the victim and stabbed him.

Young people who knew Yemurai's gathered at the scene to lay tributes for him.

Natalie, a friend of the victim, said: "Yemurai was a good guy, (he) never really got into trouble."

Those who knew Yemurai said the teenager was "funny", "caring" and "loyal to his friends".

Yemurai was the eighth teenager to be murdered in the capital since January.