Detective Senior Constable Craig Wastell, of the Warrnambool police crime investigation unit, said police were called to the premises after a 19-year-old Port Fairy man suffered a fractured skull and internal bleeding after an altercation about 10.30pm.

Paramedics transported the 19-year-old and another 22-year-old Warrnambool man, who also received minor injuries, to Warrnambool Base Hospital where they were assessed and treated.

The man with the fractured skull was then flown by an air ambulance to the Royal Melbourne Hospital in a serious condition.

The altercation happened at an industrial shed at Awabi Court in the town's west.

Detective Senior Constable Wastell said employees of a business were at the shed along with fishermen and other people.

"We have reports that there were up to 30 people there and we are still in the process of identifying all those who attended," he said.

The detective said those people seemed to be in clear breach of the state's coronavirus public gathering restrictions and could be liable for $1652 fines.

He said police collected details of 10 people who were still at the shed when officers arrived.

"It appears that some people had left that area after the altercation and we are in the process of identifying those people," he said.

Anyone with information about who was in attendance is requested to contact the Warrnambool police station or Crime Stoppers on 1800 333 000.

A 30-year-old Port Fairy man was interviewed and charged by police at the weekend with intentionally causing injury and affray.

The accused man has been bailed and will appear in Warrnambool Magistrates Court on September 21.

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