Wollongong police came across the 22-year-old lying unconscious on a footpath on the Princes Highway at around 12.30am.

He was taken to Wollongong Hospital where he remains in a critical condition with serious head injuries.

It’s believed the man was assaulted after leaving a nearby hotel.

Police were told the man then fell and hit his head on the concrete.

Detectives are attempting to establish the circumstances surrounding the incident and are appealing for anyone with information to come forward.

It is believed a number of cars and pedestrians were in the area at the time of the suspected assault and may be able to assist with inquiries.

Those with information are urged to contact Wollongong Police Station on 4226 7899 or Crime Stoppers on 1800 333 000.