A man is in hospital with a fractured skull after being attacked while dancing in a Dartford pub.
The victim, in his 20s, was involved in a row with another man in The Clipper pub, in the High Street, in the early hours of Saturday.
It is claimed the other drinker punched him in the face, knocking him to the ground unconscious, before leaving the pub.
The Clipper pub in Dartford High Street
The attacker is described as around 5ft 11in, of medium build and with short, dark hair.
He was clean-shaven and wearing a blue and white striped jumper.
The suspect was with another man, who is described as very large and wearing a grey polo shirt.
The victim, from London, suffered a fractured skull and remains in hospital after the attack, between 1am and 1.15am.
DC Kerry Thompson, from Kent Police, said: "This was a nasty and apparently unprovoked assault that has left a young man with serious injuries.
"We are trying to build up a complete picture of the circumstances leading to the incident.
"I urge anybody in the pub or who saw the suspect leaving to get in touch."
Witnesses or anyone with information is asked to phone DC Thompson on 01474 366073 or Crimestoppers, anonymously, on 0800 555111.