After starting the No. 2 engine near gate C-7, the pilot gave two hand signals to the forward stationed ground handler in succession; (1) to disconnect electrical power, and (2) to pull the chocks. The ground handler disconnected the electrical cable, closed the airplane’s ground service access door, wound the cable and stored it on its GPU mounted rack. She then proceeded directly to the right side nose area, made eye contact with the first officer, and bent down to pull the nose wheel chocks. When she pulled the forward chock, the right nose tire passed over her foot, and the aircraft rolled forward. Observing the mishap, the second ground handler ran over to pick her off the ground and they both ran forward trying to give the flight crew the emergency stop signal. The airplane continued forward about 10 to 15 feet until collision by the No. 2 propeller with the top of the GPU. The propeller was in high rpm at the time of the propeller strike. Fragments of propeller blade impacted the right side fuselage and the sudden stoppage fractured the No. 2 engine case, causing a fuel leak. A fire was ignited by flame droplets falling from the No. 2 engine intake to puddled up jet fuel under the engine and main landing gear area developed. One of the four propeller blades separated from its hub and all four blades sustained tip damage. The spinner was torn as a result of the blade separation. The propeller collision caused metal and composite fragments to impact and dent the right side fuselage. Although the aircraft is still on the US Register, the plane was reported withdrawn from use and used for spares. PROBABLE CAUSE: “The pilot’s failure to verify that the parking brake was applied prior to engine start, and the resultant inadvertent movement of the aircraft and collision with the ground power cart once No. 2 was started.”