BANGKOK (AP) -- Authorities in Laos have retrieved the cockpit voice recorder from a Lao Airlines plane that crashed into the Mekong River this month, killing all 49 people on board, but have not yet recovered the flight data recorder, officials said Thursday.
The Lao Airlines ATR-72 turboprop plane crashed Oct. 16 during a heavy storm as it approached Pakse Airport in southern Laos. It struck a riverbank before plowing into the swift-running Mekong.
The cockpit voice recorder was recovered from the river Thursday, said Yakua Lopangkao, director-general of Laos' Department of Civil Aviation, adding that the flight data recorder was still missing.
A cockpit voice recorder is used to record conversations in the cockpit, while a flight data recorder logs technical data such as the plane's altitude, speed and route.
Yakua said both devices — commonly known as black boxes — are needed for a thorough investigation.
"To be able to investigate the cause of the crash — whether it was because of technical errors or pilot errors — we need to retrieve the other black box, too," he said by phone. "Once we recover it, the investigation process can speed up."
Strong currents and deep, muddy water in the Mekong have hampered searchers.
The airline said Wednesday that 47 bodies had been found so far, and 43 of them had been identified.