BANGKOK (AP) -- Investigators in Laos said they picked up underwater signals Sunday that they believe are coming from the black box of a passenger plane that crashed into the Mekong River last week, but that strong currents were thwarting attempts to find it.
The Lao Airlines ATR-72 turboprop plane crashed Wednesday after getting caught in a heavy storm as it approached Pakse Airport in southern Laos. It struck a riverbank and then plowed into the swift-running Mekong. All 49 people on board are presumed dead.
As of Sunday, 41 bodies had been recovered, investigators said.
French air crash investigators began working at the crash zone on Saturday along with a team from the aircraft manufacturers, bringing much-needed technical expertise to the operation in one of Asia's poorest countries. Navy divers from Thailand are also helping the search.
Yakua Lopangkao, director-general of Laos' Department of Civil Aviation, said that investigators using sonar and other equipment Sunday picked up signals from underwater and narrowed their search to the area "we believe might be the location of the black box."
"But the search teams still cannot retrieve it because the water was deep and muddy and the current was very strong," he said. "At this point, we cannot find anything."
According to the airline, 44 passengers and five crew members were on the flight. The passengers included 16 Lao nationals, seven French, six Australians, five Thais, three Koreans, three Vietnamese and one person each from China, Malaysia, Taiwan and the United States.
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