Police are suggesting rural property owners should store their firearms away from their property if they intend to be away for any length of time.
This follows two separate burglaries in Victoria's West Gippsland where a thief twice stole five guns which had been left on the property.
Police are investigating the burglaries at Seaton and Glenmaggie from last month.
The trailer pictured above was also stolen during one of the thefts.
Police said on both occasions the property owners were away.
The first crime was committed on a rural property on Thompson Lane in Seaton between 5.45am and 5pm on April 10.
The thief forced entry to a gun safe, stealing five firearms and ammunition, police said.
Ten days later, a second burglary occurred inside a shed on Kellehers Road, Glenmaggie sometime over a period of 10 days.
That location was about 20km north of the first theft.
Five firearms, a trailer, a car fridge and air compressor were all stolen.
Police said the incidents "are believed to be linked" at this stage.
As a result of the thefts, police have encouraged owners of firearms to ensure they are secure and "if they are away from their property for any period of time to store them at another location".
Anyone who witnessed the incidents, has CCTV footage or information is urged to contact Crime Stoppers on 1800 333 000 or log onto www.crimestoppers.com.au