While demolishing a condemned home in Cadillac, workers found a World War I mortar.
Police were called to the home on Whaley Road and then contacted the Michigan State Police Bomb Squad.
Two bomb technicians examined the device and determined it was a British World War I 3-inch mortar and was believed to be a practice round.
They x-rayed the device and could see something was inside the chamber, but could not determine whether or not it was live.
The bomb technicians took the device to a gravel pit and shot a charge through the side of the device. They then learned that the mortar was filled with sand and was a practice round.