Relatives of those killed in the Air China plane crash began the grisly task of trying to identify the dead. But officials say many will need to give blood for D-N-A tests. The Transportation Ministry said investigators will take blood samples from the victims' families to try to match D-N-A samples extracted from badly burned bodies. Only a few of the one hundred-22 dead have so far been identified and investigators say it could take two months to complete the process for the most badly burned victims. Meanwhile, investigators from South Korea, China and the United States are trying to figure out what caused the crash. The cockpit voice and flight data recorders have been transported to Seoul for detailed analysis. The condition of the voice recorder is reportedly better than expected, with only minor dents. But parts of the flight recorder had been burnt. It is not clear whether this would hamper analysis. Officials say it would take about two months before they could find out the exact cause of the disaster, but basic outlines of the cause will be known in a few days at the earliest. Flight C-A 1-29 on a flight from Beijing ploughed into a fog-shrouded mountain Monday minutes before a scheduled landing at Kimhae Airport west of Busan. Thirty-eight of the one hundred-66 people on board survived. Six are still unaccounted for.