Police seized a gun, ammunition and balaclava after finding a van in Tuggeranong that was reported stolen a fortnight ago.
ACT Policing said on Saturday that officers ran routine checks on the white Mitsubishi Express, which was parked in Dalziel Street in Gowrie, after it was spotted with no front registration plate at about 11.20pm on Thursday.
"Police received permission from the owner to access the vehicle and found a shotgun, ammunition and other items, including torches, stolen power tools and a balaclava inside," ACT Policing said in a statement.
The van, stolen in late June, also held a gunsafe with a cut lock. A police spokeswoman said the vehicle had now been returned to its owner.
Investigations are ongoing and the items found will undergo forensic analysis. Police said it was still to be determined whether the firearm was used in committing an offence.
Anyone who witnessed suspicious activity in the Dalziel Street area on Thursday or may have information regarding the incident is urged to contact Crime Stoppers on 1800 333 000 or at act.crimestoppers.com.au. Information can be provided anonymously.
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