A man has died a week after being attacked by two teenagers he confronted for throwing litter into a car window.
Evren Anil confronted two youths for throwing litter
Evren Anil, 23, was in the front passenger seat when the pair threw rubbish through the open window as the car waited at traffic lights.
When challenged one of the youths took out a knife and Mr Anil was stabbed or punched in the face, police said.
Five people have been arrested and bailed over the attack in Central Hill, Crystal Palace, south-east London.
Mr Anil, of Upper Norwood, suffered head injuries in the attack at about midday on 5 August and died in hospital on Monday.
Police said a passer-by intervened when the youths produced a knife, but that person left the scene when threatened by the youth.
The passer-by then alerted the emergency services.
Both suspects, who were described as being black and in their late teens, ran off into the nearby Central Hill Estate.
Det Ch Insp Cliff Lyons said: "This was an excessive use of violence by two youths who apparently attacked Mr Anil because he dared to challenge their behaviour.
"He never recovered from the injuries he sustained that day and leaves behind a family trying to come to terms with their loss."