Detectives have started a murder inquiry after a man found injured on Chester's city walls died in hospital.
Christopher Garwell, 23, of Connahs Quay, Flintshire, was found with head injuries near King Charles Tower on Thursday night.
He was being treated in the Walton Centre Hospital, Liverpool, but died on Wednesday afternoon.
Four people held on suspicion of assault on Tuesday have now been re-arrested on suspicion of murder.
Police initially thought Mr Garwell had collapsed from drinking, but a scan later revealed serious head injuries.
They now believe an altercation began in the area of Charlotte Court and continued until his collapse.
Anyone who was in the area at the time - at about 2000 BST - is urged to contact Cheshire Police.
Detectives are continuing to question two 16-year-old boys, a 17-year-old and a man, aged 20, on suspicion of murder.