Parts of a pump action shotgun have been found in the Portland tip.
Detective Sergeant Jason von Tunk, of the Portland police crime investigation unit, said it was believed the parts were dumped at the tip on February 8 and have now been handed in to police by Glenelg shire recycling and landfill staff.
"Someone has dumped it. It was found in a metal bin," he said.
"There are correct ways of disposing of firearms and that's through Victoria Police, not the tip."
The investigator said the parts located included the firing mechanism and barrel but not the butt or grip.
"It's not operable. It's in a rusty condition and investigations are continuing into whether it could be made operable," he said.
"The serial number has also been removed."
Detective Sergeant von Tunk requested that anyone with information about the firearm parts contact the Portland police station or Crime Stoppers on 1800 333 000.
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