By Tiffany Stockton,

OKLAHOMA CITY -- A man called police after he said he dug up what he thought was a grenade in his yard.

Stephen Mayo said he was digging in his garden when he heard a distinct "ping" sound. He said he thought he had hit a rock, but then he uncovered what appeared to be a grenade.

"I pulled it up and there it was. It was green and kind of old, and I said we've got to get out of here. We've got to call the police, call the bomb squad because it was like frightening. It could have blown us up," Mayo said.

Authorities haven't said whether the possible grenade posed any threat.

The bomb squad will take the object out to a range where they will dispose of it and will determine if it had any explosive properties to it.