Soldiers taking part in a military exercise in Sydney, N.S., got a surprise Monday when a vehicle pulled up to their camp near Open Hearth Park and dropped off an unexploded artillery shell.

"Just slightly after lunch there was a vehicle dropped off an unexploded ordnance at the gate of the main operating base for exercise … and the device was actually described as a projectile," said Capt. Jamie Tobin, a public affairs officer with the engineer support regiment.

Tobin described the ordnance as a "large round" or "artillery." He said the Cape Breton Regional Police, with the assistance of the engineers support unit, is investigating to determine who dropped off the shell. He said the Cape Breton Regional Municipality was also contacted.

"One of our units is actually managing the containment of the device in co-operation with the Cape Breton Regional Municipality and an unexploded ordnance specialist is coming up from Halifax. They will be determining disposal measures," said Tobin.

Tobin said he did not know the age of the shell. He said the unexploded ordnance does not pose any risk to the public and urged anyone with information to contact the police.​