Detectives investigating a city centre assault which left a man critically ill were today questioning three men.
A 23-year-old man was arrested over the attack in Foyle Street, Derry, in the early hours of yesterday.
Another two men, both in their 20s, who were arrested after the assault, remained in custody.
The 27-year-old victim was in a critical condition in hospital.
Police were called to the scene of the assault near a bookmaker's shop at 2.15am.