UP to 10 offenders wearing balaclavas robbed a unit in The Ambassador complex, Frankston, 10.40pm, Saturday 9 December.
A resident, 38, told police he answered a knock at his door and was shocked to see two men wearing balaclavas standing outside. They forced their way in before knocking him to the ground and beating him.
The man managed to break free and escape and ran along Nepean Highway to the police station.
Officers formed a cordon around the complex but the men had gone. Neighbours said they saw six men wearing balaclavas but police believe the number may be as high as 10.
Anyone with information is urged to call Crime Stoppers 1800 333 000.