England: A Somali immigrant has been given a life sentence for murdering 15-year-old schoolboy footballer Kiyan Prince
Hannad Hasan, 17, stabbed Kiyan in the heart when he intervened in a play fight outside the London Academy School in Edgware, north London, in May 2006.
Hasan, from Colindale, north London, admitted manslaughter but denied murder, claiming it was an accident.
He was told at the Old Bailey he would have to serve at least 13 years after being convicted of murder on 2 July.
Hasan, who went to the same school as Kiyan but was in the year above, trapped the teenager in a headlock and produced a penknife which he described as a "little toy" which he used to stab the victim in his heart.
The court had heard that less than two weeks before the stabbing Hasan had threatened to stab a girl during a trivial dispute over a bus seat.
The police and the Crown Prosecution Service are holding an inquiry into a "catastrophic" failure which meant the court could not hear evidence about this.
In addition, six days before stabbing Kiyan, Hasan had been excluded from his school for assaulting pupils and urinating in front of a teacher.
At the Old Bailey on Thursday, Judge Paul Worsley said Hasan, who lived with his mother, would only be released when it was clear that he was no longer a risk to the public.
On release, the judge said Hasan, who was said to be obsessed with Somalian gang culture, including the gang that killed Pc Sharon Beshenivsky, would then be deported to his native Somalia.
"This is yet another case of a wholly unprovoked stabbing in a public place, by a person who produced a knife and plunged it into the heart of their unarmed victim."
He added: "Taking the life of another is always a terrible thing, taking the life of a talented, popular 15-year-old schoolboy who was known to you and who had done you no wrong and had everything to live for defies description.
"You have deprived his family and schoolfriends of a role model."
Det Ch Insp Alistair Tully, from the Metropolitan Police said: "Kiyan Prince was a young man with everything to live for. He was a talented footballer and all-round athlete. His life was cut short by another young man who was all too willing to arm himself with a knife in a show of bravado.
"He held Kiyan in a headlock before stabbing him twice, once in the arm, the other in the chest, which resulted in Kiyan's death.
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