Warrnambool police station was closed to the public for much of Sunday after a woman handed in a grenade that still had the ignition pin inserted.
Sergeant Chris Brown of Warrnambool police said police taped off the entrance to the station in Koroit Street from about 9.30am until about 3pm when an Australian Army officer took the grenade away.
Media reports said the woman told police the grenade had been on a shelf at her home for 10 years after it was given to her by her father-in-law.
Police sent photos of the grenade to the bomb response unit, which called in the Australian Army that sent an officer from Melbourne to collect it.
Sergeant Brown said the grenade was placed in a secure area until it was collected.
He said that if people found what they believed was live ordnance, they should leave it in place and contact the police.