Homicide detectives have launched an appeal for witnesses following the murder of 15-year-old boy named locally as Quamari Barnes.
Detectives from the Metropolitan Police Homicide and Major Crime Command are urging parents and children who would have been going home from school at the time to help with their investigation.
An incident room has opened under detective chief inspector Mark Lawson.
DCI Lawson, said: "The area around Doyle Gardens and Uffington Road was very busy at the time of the murder.
"A large number of children were going home from school.
"I would like to hear from them, or their parents, as I'm certain that people will have information that could prove vital to the investigation.
"Whilst the motive for this stabbing remains unclear, I would also like to speak with anyone who may have heard about what happened after the attack."
A statement from Capital City Academy made this morning (Tuesday January 24) said: "It is with overwhelming sadness that Capital City Academy must confirm the sudden death of one of its students on Monday 23rd January.
"Our thoughts and prayers are with the family at this very sad time; and also with friends, fellow students and teachers.
"Capital City Academy will be offering a counselling service to students and staff.
"If anyone has any information relating to this tragic event please contact the Police via 101.
"To give information anonymously contact Crimestoppers 0800 555 111."
The teenage boy was found suffering from stab wounds and was rushed to hospital where he died.
Next of kin have been informed but formal identification awaits.
A post-mortem examination will be held in due course.
Any witnesses or anyone with any information is urged to call the incident on room on 020 8358 0200 or via 101 or by tweeting @MetCC
To give information anonymously contact Crimestoppers on 0800 555 111.
No arrests have been made and police enquiries continue.
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