A man was in a critical condition on Friday after he was attacked while leaving a nightclub in Blackpool.
The 19-year-old was assaulted by a man in Church Street, near St John's Church.
The victim, who had just left the Syndicate club, was knocked to the ground and suffered a serious head injury.
He was taken to Blackpool Victoria Hospital where he was being treated in the intensive care unit.
Lancashire Police appealed for a woman, who was seen with the victim remonstrating with his attacker, to come forward.
She had dark hair, was aged about 18, and wore a white top.
Detectives have studied CCTV footage and interviewed people who were at the club.
The man, who is from the Blackpool area, has not been named.