The body of Donna Bunting, 16, of Chesterfield was discovered on Sunday morning behind the Bradbury Club in the town.
Derbyshire Police said she had serious head injuries caused by a "vicious attack" with a blunt instrument, which did not appear to have been sexually motivated. Her body was found by nightclub staff in an alley behind the club where detectives believe she was murdered.
Police said yesterday that Donna arrived at the club with a female friend after 10pm on Saturday, having earlier been to a number of pubs in the town. She did not have a boyfriend and it is not known if she left the club with anyone. Detective Superintendent John Langley said Donna's parents did not know she was planning to go to the club - which is for over 18s.
He told a press conference: "We think at 10pm she was still in the town centre and moved on to the nightclub sometime after that.
"She was with this friend in the club and spoke to a number of other people, both male and female."
Donna lived with her parents and 25-year-old brother. She also had a 27-year-old sister. Det Supt Langley appealed for anyone who saw her on Saturday night or has any information to contact them.