Several roads in downtown Jacksonville were closed after a suspicious item was found Tuesday, JSO says.
Monroe Street and Duval Street have since reopened.
A tenant at a neighboring building said he found what appeared to be an old grenade while cleaning out a building.
That unit evaluated the item and determined it was not a grenade and did not contain any explosives, JSO said.
JSO says patrol officers evacuated nearby businesses and secured the scene while waiting for the hazardous devices unit.
The scene was determined to be safe and JSO cleared the area.