A teenager suffered serious facial injuries in an attack in a Sheffield nightclub.
The 17-year-old was assaulted in the Area nightclub in Burgess Street, Sheffield city centre, on Sunday, February 5.
South Yorkshire Police said he suffered serious injuries to his mouth and face in the attack following an altercation in the club.
His attacker was white, in his early 20s, around 6ft 2ins tall, of a stocky build and had dark brown hair.
He was wearing light coloured T-shirt.
A South Yorkshire Police spokesman said: "Police in Sheffield are appealing for witnesses following a reported assault at Area nightclub, Burgess Street, Sheffield.
"It has been reported that at around 1.10am on Sunday, February 5 a 17-year-old boy was assaulted by an unknown man, following an altercation in the nightclub.
"The 17-year-old suffered serious injuries to his mouth and face in the attack and police would like to speak to anyone who may have been in the nightclub at the time, or witnesses to the reported attack."
Call South Yorkshire Police on 101.