A traffic stop near St. Marys lead to impaired driving and weapons charges.
OPP pulled over a Dodge Ram on Highway 7 after determining the vehicle was travelling significantly slower than the speed limit.
OPP say they arrested a man after a driver failed a roadside breath test.
A search of the vehicle turned up a loaded firearm.
Police seized both the gun and ammunition.
31 year old Cho Lay of Perth South faces charges.