It sounds like standard radio chatter between an airplane and ground control, mostly repeating the identifying number of the flight.
But the recording that Malaysian officials played for the first time in public in a Beijing conference room on Tuesday is purportedly the last known words of Malaysia Airlines Flight 370 before it disappeared on March 8.
"Malaysia three-seven-zero contact Ho Chi Minh 120.9, good night," says a voice identified by Malaysian officials as that of a radar controller in Kuala Lumpur, the Malaysian capital.
"Good night Malaysian three-seven-zero," answers a male voice believed to be a crew member on the plane.
Malaysian officials released the audio recording more than 50 days after the plane disappeared, in a long-awaited briefing before scores of relatives of the flight's Chinese passengers.
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