UPDATE, 2.15pm: The Victoria Police bomb squad officers have deemed the cannonballs suspected of being live to be safe.
"The ordinance has been deemed safe," a police spokesman said.
Earlier: Victoria Police bomb squad officers are being called on to provide information and advice after a suspected live exploding cannonball rolled out of a cannon at Port Fairy.
Port Fairy police Senior Constable Andrew Macmillan said four cannons near the Moyne River at Battery Hill were in the process of being cleaned on Thursday.
Two cannons had been cleaned and as the cleaning process started on the third cannon a cannonball or remnants of a cannon ball fell out of a cannon.
Further investigations revealed that there could be between six and eight cannon balls in the remaining two cannons.
Photos of the cannons and cannonballs have now been sent to members of the police bomb squad.
"Members of the Port Fairy Historical Society were getting ready to clean the innards of the two remaining cannons when one ball rolled out," Senior Constable Macmillan said.
"There looks like there could be six or eight in each of the remaining cannons.
"The two that have been cleaned are completely empty."
The police officer said cannons on the raised embankment of Battery Hill were fired quite regularly.
The cannons involved in Thursday cleaning were on the lower level near the Moyne River.
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