A 15-year-old boy has been stabbed to death outside the gates of his London school.
The teenager, named locally as Kiyan Prince, a footballer for Queens Park Rangers youth team, was attacked in front of terrified staff and pupils just outside the London Academy in Edgware, north London.
Police said the boy had been involved in an altercation outside the school gates with another boy who fled towards a nearby block of flats. No one has been arrested, a weapon has not been found and the motive for the stabbing is unclear, but detectives said they were following several "positive lines of inquiry".
Flowers and tribute notes were laid by the school gates, as traumatised teachers and pupils paid tribute to a pupil who was "idolised" at school.
Phil Hearne, principal of the academy, said: "This was a 15-year-old boy, a young man who had the whole world in front of him and it has been taken away. He was looked up to by youngsters here, terribly well respected, an extremely reliable, hard working, bright young man. A natural born leader."
Adele Cook, the mother of a pupil at the school, said Kiyan played for QPR's youth team three times a week. "He was a great player, strong fast and powerful," she said.
A tribute note read: "Kiyan RIP. I've known you from primary school and I remember you was put in my class. You was always so funny."
The London Academy is one of Prime Minister Tony Blair's flagship city academies. Earlier this year, Ofsted inspectors said it had delivered "exceptional" results. Despite being in a deprived area, it has risen to the top 5 per cent of schools in England for achievement.
The death comes a week after Special Constable Nisha Patel-Nasri was stabbed to death outside her home in Wembley, also north west London. The killing echoes the murder of 14-year-old Luke Walmsley, stabbed to death by a fellow pupil at Birkbeck Secondary School in North Somercotes, Lincolnshire in November 2003 during a break in lessons.
His killer, Alan Pennell, 16, who thrust a 7cm lock knife into Luke's heart following a disagreement, was found guilty of murder and detained for life in 2004.
Victims of Crime Trust director Norman Brennan said knife crime has "spiralled out of control on the streets of Britain".
"We need to bring in mandatory prison sentencing and make carrying a knife as anti-social as carrying a gun," he said.