At about 06:40 EST, a Boeing 737-3B7 operated by U.S. Airways had a flight attendant-initiated evacuation after pushback from the gate. No one was injured. U.S. Airways reported that the No. 2 engine had been bore scoped the night before and its ignition circuit breakers were pulled. The crew attempted to start the engine after pushback for the first flight of the day but was unable to. The maintenance crew told the crew to check the circuit breakers, which had not been reset. The crew started the engine and flames shot out the back. A nonrevenue flight attendant seated in the aft cabin saw the flames and told the flight attendant on duty in the back of the airplane that the engine was on fire. The flight attendant on duty opened both aft cabin doors and deployed both slides. The flightcrew piloting the aircraft was unaware of the evacuation until they were told by the ground crew attending to the airplane.