Bashed NSW man 'extremely critical'

A NSW man who was found unconscious on a footpath in the state's north is clinging to life in hospital as detectives form a strike force to hunt down his attacker.

Aaron Marks, 38, is believed to have left a pub on River Street in Ballina before midnight on Saturday.

He was found by a member of the public unconscious some two hours later having suffered head injuries.

Mr Marks was taken to Gold Coast University Hospital where he remains in an "extremely critical condition", NSW Police said in a statement on Tuesday.

Investigators have released CCTV footage showing Mr Marks leaving the pub and are urging anyone who was in the area to come forward.