What was found
DESCENDING THROUGH FL 180, EXPERIENCED LEFT ENGINE LOSS OF POWER. ADVANCING THE POWER LEVER HAD NO AFFECT ON ENGINE POWER. ALL ENGINE INDICATIONS CONTINUED TO ROLL BACK UNTIL ENGINE WAS NO LONGER PRODUCING POWER. CHECKLIST WAS FOLLOWED. ENGINE WAS SECURED AND FEATHERED. AN AIR START ATTEMPT OF THE LEFT ENGINE PRODUCED THE SAME RESULTS. AN EMERGENCY WAS DECLARED AND DIVERTED TO KMDT. SINGLE ENGINE LANDING WAS UNEVENTFUL. AIRCRAFT IS CURRENTLY IN MAINTENANCE. SDR SUPPLEMENT TO FOLLOW.