POLICE have collected forensic evidence at the Sandy Beach scene where a man was found unconscious on the road on Saturday suffering serious head trauma.
The 30-year-old Sandy Beach man remains in a critical condition as police investigated what had caused his injuries.
He was found by officers unconscious on Graham Dr on Saturday around 11pm.
It is known that the man had attended a gathering earlier that night prior to being injured.
Police say it is still unknown at this stage whether they are dealing with an assault, a motor vehicle accident or possibly injury by misadventure.
Detectives appealed for public assistance as the man clung to life in Sydney's Royal North Shore Hospital.
Police units, detectives and the dog squad established a crime scene at a nearby home this morning.
The Coffs Clarence Operational Support Group combed nearby bushland looking for evidence.
Anyone who witnessed the events of Saturday night or who may have information to assist police should call Crime Stoppers on 1800 333 000.
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