16-year-old sentenced to life for stabbing schoolboy to death in 'revenge attack'

A 16-year-old boy who killed a 14-year-old by stabbing him as he lay pleading for his life on a London pavement was yesterday sentenced to life imprisonment and told he would serve a minimum of 12 years.

Joseph Chin was found guilty of murder at the Old Bailey last month and yesterday was led from the dock to his detention after killing schoolboy Martin Dinnegan in June last year. Killer and victim were part of two groups of youths that had exchanged dirty looks just one hour before. Kevron Williams, 17, who was convicted of attempting to cause grievous bodily harm, was given four years in youth detention.

Dinnegan had been on a bus with friends when they swapped stares with a group of youths on bicycles. When they got off the bus, a fight began between the groups and Dinnegan was chased. He held out his hands in a bid to placate his attacker but fell down after he was punched in the head. Chin pinned him to the ground before stabbing him four times in the back.

Judge Brian Barker said: "The public have every right to be concerned about the increased growth of 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."

He went on: "This was a deliberate attack requiring a long chase with revenge in mind. This was really arrogant group violence and the result is totally unacceptable. It was an attack carried out without any regard to the standards and rules that we live by and no thought for the victim, his friends and his family."

The judge told Chin: "I have little doubt that you are a willful individual. You are prone to anger. You have shown a tendency to use violence when it suits you."

He told Williams he had been acting with "immaturity coupled with a misguided sense of principality and loyalty".

Chin stabbed Dinnegan after being knifed twice himself during a series of flare-ups between the two groups.

The judge told him: "This was a vengeful attack out of all proportion to what may have gone on before and no mercy was shown."

Chin had a criminal record dating back to 2004, including threatening a man with a hollow bar. In September 2006 he was given a 12-month supervision order after kicking a shopkeeper unconscious when challenged for stealing food. He was still under the order when Martin died the following June.

In a statement read to the court, Martin's mother Lorraine said: "Martin was a charming, loving boy who has left us with cherished memories that will remain with us forever.

"The pain that Martin's death has caused for our family is indescribable. Life will never be the same, a piece of our heart has been taken. We as a family will never make sense of the unnecessary suffering that was inflicted upon Martin. It was extremely sad to be burying Martin at the tender age of 14."

Acting detective chief inspector Stewart Hill said: "The murder of Martin highlights the potentially fatal consequences that may result from carrying knives and other weapons. In this case an innocuous meeting of two groups of youths escalated into a series of confrontations resulting in Martin's tragic murder. "

Prosecutor Aftab Jafferjee QC said: "This case graphically illustrates the growing scourge of urban posturing, which includes the aimless meandering among groups of people who are prepared to, if not actively seeking confrontation, exploit any pretext in order to engage in aggressive violent behaviour."