What was found
(CAN) CLIMBING THROUGH FL120, THE FLIGHT CREW HEARD A GRINDING NOISE, FELT A YAW TO THE LEFT, SAW THE NR 1 GENERATOR LIGHT ILLUMINATE AND OBSERVED FLAMES AND SPARKS COMING OUT THE NR 1 ENGINE EXHAUST STACK. THE ENGINE WAS SHUTDOWN, A SINGLE ENGINE APPROACH AND LANDING WAS ACCOMPLISHED AT THE DEPARTURE POINT. NO DETAILS ON ENGINE CONDITION ARE AVAILABLE AT THIS TIME.