On 3 June a 17-year-old youth was arrested on suspicion of murder at an address in Seven Sisters Road, N4. He has been taken to an east London police station where he is currently detained.
33-year-old Barış Küçük was stabbed in a suspected street robbery at the weekend lost his fight for life in hospital.
Küçük was stabbed in the leg in Haringey by a thug apparently trying to steal his mobile phone.
Police and paramedics were called to the scene in Seven Sisters Road shortly after 3 am on Saturday. Mr Küçük was taken to a north London hospital but died on Monday.
Police ask that anyone who has information that could assist police is asked to call 101 ref CAD 1360/1JUN, Tweet @MetCC or call Crimestoppers anonymously on 0800 555 111.