Senior Constable Ross Hatton, of the Warrnambool police crime investigation unit, said unknown offenders broke into Timboon Motors on Timboon's Bailey Street overnight on Saturday.

"There's been a smash-and-grab at the car dealership, where the unknown offenders, or offender, have smashed the glass sliding doors at the front of the shop," he said.

"They've entered the show room and grabbed a whole bunch of stuff, including chainsaws, brush cutters and pressure washers."

The stolen items are believed to worth more than $10,000.

Senior Constable Hatton said the business owners were forced to shut for a short time as they cleaned up.

He said police were still waiting to find out exactly what was stolen and the total damage bill.

Senior Constable Hatton said police believed a utility was involved in the break-in.

"We are appealing for any witnesses that may have seen any strange vehicles or people hanging around the dealership in the early hours of Sunday morning," he said.

Anyone with information is urged to contact the Warrnambool police crime investigation unit on 5560 1333 or Crime Stoppers on 1800 333 000.

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