Detective Acting Sergeant Wayne Ryan, of the Warrnambool police crime investigation unit, said that overnight last Thursday offenders broke into the yard.

"It is not known if anything stolen from one of the onsite storage facilities," he said.

At about 3pm Friday and unknown offender attended at the same business and stole an advertising sign valued at $50 from the property.

"A male described as being about 30 years old with a beard is a person of interest in relation to the burglary and the theft," Detective Acting Sergeant Ryan.

"He was seen sitting on a bike with two younger males about 3pm and then again later that afternoon. 

"Anyone who has information into about the identity of the man with the beard or the burglary and theft is requested to contact the Warrnambool police station or Crime Stoppers on 1800 333 000," he said.