A victim chased off a thief who was rifling through a vehicle in Longwarry in the early hours of Thursday morning.
Police said two unlocked vehicles were targeted in Bandicoot Crt and Bilby St at about 1am.
They believe the offender was travelling in a silver Holden Commodore with no registration plates.
At Bandicoot Crt, a victim ran outside and chased the offender away from his vehicle.
The Holden Commodore was linked to a burglary at Drouin Golf Club on the same night.
Police believe it was used to smash roller doors to a storage shed. Power tools were stolen from inside.
The incident occurred between 2pm on Wednesday and 5.40am on Thursday.