Detectives investigating the murder of Gabriel Petrov Stoyanov in Downham have named a youth they want to speak to in connection with his murder.
George David, 16, from Downham, is wanted on suspicion of murder.
He has links to Bromley and Orpington.
Anyone who sees him is urged to call 999 immediately, reference CAD 8645/4 Nov. He should not be approached by members of the public.
Information as to his whereabouts can be given to 101 or tweeted @MetCC using the same reference.
Detective Chief Inspector Kelly Allen, investigating, said: “Two arrests have been made as part of our investigation but we urgently need to speak to George David. Officers from across the Met are working to trace him.
“George, my message directly to you is that you must attend a police station immediately.
“We believe it’s possible George is being hidden or moved around by people he knows. My message to those people is that if you are working to frustrate our enquiries you should be very much aware of the trouble you could find yourself in. We will seek to arrest and prosecute you to the fullest extent of the law.”
A murder investigation was launched after Gabriel was stabbed in Bromley Road, Downham following an incident shortly before midnight on Friday, 4 November.
Officers attended along with colleagues from the London Ambulance Service.
They found 21-year-old Gabriel suffering a stab injury. He was taken to hospital for treatment but died during the afternoon of Saturday, 5 November.
A 17-year-old man [B] was arrested on Thursday, 10 November on suspicion of murder; he remains in custody at a south London police station.
A 14-year-old boy [A] who was arrested on Tuesday, 8 November on suspicion of murder remains in custody after a warrant for further detention was authorised.