At 8:10am, the USRFD was dispatched to a motor vehicle crash with rollover on Route 17 North. Chief Vierheilig (IC) arrived on scene to find one vehicle with heavy front end damage and another on its roof. With all occupants out prior to arrival, orders were given to Rescue 1242 (OIC Capt Sklar) for the crew to secure and stabilize the vehicles and contain the fluid spill on roadway. Engine 1232 (OIC FF S Roberts) was also in scene. While doing a scene survey, a mortar shell was found next to the rolled over vehicle. A safe area was established and units awaited a response from the Bergen County Police Bomb Squad. Once the ordinance was contained and removed, fire personnel assisted the tow crews with vehicle removal and debris cleanup. Once clear, all units returned to HQ.