Mangalore, India (CNN) -- Searchers continued sifting through twisted metal, charred debris and tattered clothing in a ravine in southern India Monday, looking for the missing piece investigators hope will explain what went wrong in a deadly plane crash.
India's civil aviation authority said officials have found two key items that will help them piece together the last minutes of Air India Flight IX-812: the cockpit voice recorder and the digital flight acquisition unit.
But on Monday they were combing the rubble for the flight data recorder -- commonly known as the "black box."
S.N.A. Zaidi, the head of India's civil aviation regulator, told CNN Sunday that it could be months before authorities can determine what caused the plane to overshoot the runway at Mangalore International Airport, hit a barrier wall and crash into a valley on Saturday morning.
The crash killed 158 of the 166 people on board the Boeing 737 passenger jet, which took off from Dubai, United Arab Emirates, and crashed while trying to make its scheduled landing in Mangalore. Eight people survived the crash.