What was found
AIR RETURN: DURING FLIGHT FROM SKGT TO SKBO AT 28,000 FEET, FWD ENTRY DOOR LIGHT ILLUMINATED WITH EICAS MESSAGE. FLIGHT ATTENDANT REPORTED THE DOOR HANDLE COMING OUT OF LOCKED POSITION AND STRONG NOISE. CABIN ALTITUDE INCREASED RAPIDLY, BUT WAS CONTROLLED IN MANUAL. EMERGENCY DESCENT EXECUTED. CABIN ALT DID NOT EXCEDE 10,000 FEET. AIRCRAFT RETURNED TO SKGT. CHECKED DOOR LOCK MECHANISM, AND FOUND LOCK OF THE DOOR LEVER (EXTERIOR SIDE) UNLOCKED. IT WAS REPOSITIONED. (X)