A fourth person has been arrested on suspicion of murdering an 18-year-old man who was stabbed in Manchester.
Sait Mboob died on 8 August following reports of a fight on Crosshill Road, Moss Side.
Greater Manchester Police said an 18-year-old man was held and remains in police custody.
Earlier this week a 17-year-old boy was charged with murder and three counts of attempted murder in connection with Mr Mboob's death.
Another 17-year-old boy and a 32-year-old man, who were earlier held on suspicion of murder, were released while inquiries continue.
Mr Mboob was described by his family as "intelligent and talented".
A post-mortem examination concluded he died from stab wounds.