Marshfield police say two fireworks-mortar shells taped to P-V-C pipe caused Thursday’s bomb scare. Nobody was injured and there were no explosions. The device was found in the front yard of a home and the resident called police. An investigation found what is being called a suspicious device. P-V-C piping had been taped together with two-inch fireworks mortars and they were aimed at the house. The Marathon County Bomb Squad deployed and X-rayed the device. Charring indicated one or more of the mortars may have ignited, but no damage was done. Police say they have a person of interest in the case, but no names have been released.