Police today named a 17-year-old boy stabbed to death as Kwame Ofosu-Asare.
The teenager was discovered on early Friday evening with stab wounds in Adelaide Close, Moorlands Estate, Brixton, London.
He and a friend were chased by two knifemen, police said.
The boy, who lived in Catford, south east London, was en route to hospital when he died in the ambulance.
A post-mortem at Greenwich mortuary today gave cause of death as multiple stab wounds.
It is believed Kwame - a sixth form student - and his friend were on their way to the friend's relative's house when they were chased by two young men and assaulted. Kwame's friend was not injured.
The suspects are described as two young black men.
Detective Chief Inspector John McFarlane said: "Kwame was an innocent young man enjoying himself on a Friday afternoon when he was pursued and attacked by two knifemen.
"I am appealing for anybody who was in or around the Moorlands Estate at that time and may have any information to come forward.
"Did you see or hear anything suspicious? Do you know who may have been involved?"
Officers are investigating if the killing is linked to another stabbing on Friday when a 17-year-old boy was attacked outside Norwood Bus Garage, Ernest Avenue, West Norwood at around 1.15pm.
He is in a stable condition in hospital.
Anyone with information should call the incident room on 020 8721 4205; if you wish to remain anonymous call Crimestoppers on 0800 555 111.