PULLING 1998 TOYOTA CAMRY INTO PARKING SPACE. FOOT ON BRAKE. PUT INTO PARK. CAR SUDDENLY BEGAN ACCELERATING. TRIED REVERSE, DIDN'T STOP. TRIED PARK AGAIN STANDING ON BRAKES. DIDN'T STOP. WENT OVER CURB DOWN HILL INTO CREEK. AIR BAGS DID NOT DEPLOY WHEN FRONT OF CAR HIT BANK OF CREEK. SAW PUFF OF SMOKE AFTER HITTING BANK COME FROM UNDER CAR. TURNED CAR OFF IMMEDIATELY. *NM