A teenager has been handed a life sentence for stabbing a schoolboy to death for "looking at him the wrong way".

Joseph Chin, 16, was today given a life sentence and has been ordered to serve a minimum of 12 years for the murder of schoolboy Martin Dinnegan in London, in June 2007.

A ban preventing the identity of Chin being revealed was lifted by a judge at the Old Bailey.

The court heard that Martin, 14, was chased and stabbed near his home in Holloway, north London, after exchanging "dirty looks" with a gang.

Chin was found guilty last month of stabbing Martin four times in the back for "making faces" and "straying into the wrong postcode".

Martin was with a group of friends who became involved in an altercation with another group of about 15-20 youths following a "verbal exchange".

A 17-year-old found guilty of attempting to cause grievous bodily harm is awaiting sentence for the attack.

Judge Brian Barker, the Common Serjeant of London, said: "The public have every right to be concerned about the increase growth in this sort of violence.

"It is a tragedy that this sort of triviality caused such a young man to lose his life and has caused enduring heartache to his friends and family."

Martin's parents have called on Prime Minister Gordon Brown to put an end to Britain's "rampant" knife culture.

Martin's mother, Lorraine Dinnegan, 39, said at the time of her son's death: "Martin was a lovely boy. He did not deserve this. It is horrendous. We are totally shattered that this has happened."

(DS/JM)