Police said Jimmy was trying to avoid a fight when he was attacked
London Mayor Boris Johnson has said there is a need to "change the mentality" of youths in the wake of the murder of schoolboy Jimmy Mizen.
Jimmy, 16, was slashed with a shard of glass at a bakery in Lee in south-east London, 500 yards from his home.
Mr Johnson said there would be "zero tolerance" to crime and stressed the need to introduce hand-held scanners to detect weapons in the capital.
He pledged to bring in the technology during his successful mayoral campaign.
Mr Johnson said: "We have got to change the mentality of these kids lured into such destructive choices.
"Everybody is shocked by the level of violence we are seeing, particularly towards young people in London.
"We are having meetings with the Met to see where we can get the scanners out where we need them... actually lifting the guns and knives off people on the streets."
Jimmy, who was killed the day after his 16th birthday, is the 13th teenager to have been fatally attacked in London since the start of the year.
Speaking on Radio Two, one of Jimmy's six brothers, Danny, 30, said: "There was no airs or graces or anything about Jimmy. What you saw is what you got.
"He was such a...he was a loving, genuine boy.
"He was an absolute star... he was our absolute favourite, ok? We all had such a connection with him."
Jimmy also had two sisters.
Earlier, Scotland Yard refused to comment on reports a 19-year-old suspect in the teenager's murder has fled to Northern Cyprus.
Press reports said an arrest warrant had been issued for a young Turkish man in connection with the stabbing.
Police are still interviewing a "significant witness", a man said to have seen part of the attack.
Det Ch Insp Cliff Lyons, who is leading the investigation, said officers had gathered CCTV footage and forensic evidence.
Mr Lyons has stressed the murder was not race or gang-related.
Jimmy who lived with his family in Dallinger Road, Lee, had been due to start an apprenticeship in Southwark Council's housing and maintenance department.