O/O 1 WAS HUNTING WATERFOWL ON RED LAKE WITH ANOTHER GROUP OF INDIVIDUALS IN A SEPARATE BOAT.  SECOND VESSEL LEFT THE AREA, O/O 1 STAYED IN ORIGINAL SPOT WEST OF THE BOAT LANDING ON THE SOUTH SIDE OF THE LAKE.  APPROXIMATELY 30 MINUTES AFTER LEAVING, THE SECOND VESSEL RETURNED TO THE ORIGINAL AREA AND FOUND VESSEL 1 CAPSIZED APPROXIMATELY 100 YARDS NW OF THE BOAT LANDING.  THE OCCUPANTS OF THE SECOND VESSEL COULD NOT INITIALLY LOCATE O/O 1, HOWEVER LOCATED HIM SEVERAL HUNDRED YARDS DOWNWIND OF THE BOAT, HAVING WASHED UP ON SHORE.  

CPR WAS PERFORMED BY THE OCCUPANTS OF THE SECOND VESSEL AND BY MEDICAL PERSONAL UPON ARRIVAL, SUBJECT WAS NEVER REVIVED.

O/O 1'S STOMACH WAS PUMPED IN THE AMBULANCE, UPON ATTEMPTING TO PUMP THE STOMACH A TWIST OFF BOTTLE CAP WAS REMOVED FROM THE SUBJECTS AIRWAY.

CURRENT ASSUMPTION IS O/O 1 CHOKED ON THE BOTTLE CAP, LOST CONSCIOUSNESS AND EITHER FELL OVERBOARD IMMEDIATELY, OR THE BOAT CAPSIZED WITH THE SUBJECT STILL IN IT.
CHAMBERLAIN                   