Detective Senior Constable Richard Hughes, of the Warrnambool police crime investigation unit, said an unknown offender entered a newly built Metricon home in Bowen Street between Saturday and Monday.

"The house is just built and was in handover stage," he said.

"The offender is believed to have used an electric saw across three panels of a wall, causing approximately $1000 damage."

The detective said the house was believed to be locked and there was no sign of forced entry.

He said the offender appeared to have cut about 10 millimetres into the wooden panels

He said no power tools were left at the site.

Detective Senior Constable Hughes said the same damage occurred on May 27 but was not reported.

He said new panels were installed on July 9 - just days before the repeat offending.

"All the panels will need to be pulled out and replaced," the detective said.

Anyone with information is urged to contact Warrnambool police or Crime Stoppers.

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