A Geraldton man in the regional town was king-hit outside a nightclub was flown to Perth early this morning.

At about 4.30 am, according to police, outside a nightclub at Fitzgerald St, the man was found unconscious.

Doctors at the Geraldton Regional Hospital to relieve swelling on his brain had to drill into his head.

Later in the morning hours, the Royal Flying Doctor Service flew the man to Perth.

The injuries could not be known but he is admitted at the Royal Perth Hospital and is in a stable condition.

Police sources stated about how the man was injured that he was left injured on the footpath after being punched in the back of the head.

A person of interest has been interviewed, Sgt Gerry Cassidy from Geraldton police stated but at this stage no one has been charged at this stage leading to no arrests.

A similar incident in which a man was punched outside the nightclub had happened an hour before the incident happened and to diffuse the altercation, the police was called in.

At the moment the case is being investigated by Geraldton detectives.