AS I WAS LEAVING MY JOB'S PARKING LOT I STARTED MY VEHICLE AND PROCEEDED TO PUT MY QX60 IN REVERSE AND MY ENGINE REVED SO VERY VERY LOUD THAT IT SCARED ME TREMENDOUSLY. THE TRUCK TOOK OFF ON ITS OWN, WHILE TRYING TO STOP THE VEHICLE IT CONTINUED TO SPEED IN REVERSE UNTIL I HIT A BRICK WALL. THEN WITHOUT ME TOUCHING THE GEAR SHIFTER THE VEHICLE PROCEEDED TO GO FORWARD ON ITS OWN AND DIDN'T STOP UNTIL MY VEHICLE WENT INTO A RAVINE.