Egyptian investigators say there was smoke on board the EgyptAir plane that went down on May 19, killing all 66 people aboard.

Investigators were able to successfully download information from the flight data recorder, and they say preliminary information shows that it was able to record the entirety of the flight.

They hope the data on the two recorders — recovered from the sea two weeks ago — will shed some light on the cause of the crash, which remains a mystery. So far, there have been no claims of responsibility for bringing down EgyptAir Flight 804, and no distress call was made from the plane.

As NPR's Eleanor Beardsley reports, "Automated electronic messages sent by the plane just minutes before it disappeared showed that smoke detectors went off in a toilet and in the avionics section below the cockpit."

A statement from the Egyptian investigators says the new information from the flight recorder is consistent with these Aircraft Communications Addressing and Reporting System messages. They were first published by The Aviation Herald:

"00:26Z 3044 ANTI ICE R WINDOW 00:26Z 561200 R SLIDING WINDOW SENSOR 00:26Z 2600 SMOKE LAVATORY SMOKE 00:27Z 2600 AVIONICS SMOKE 00:28Z 561100 R FIXED WINDOW SENSOR 00:29Z 2200 AUTO FLT FCU 2 FAULT 00:29Z 2700 F/CTL SEC 3 FAULT no further ACARS messages were received"

As Eleanor reports, "The voice and flight data recorders, often referred to as the 'black boxes,' were recovered from a depth of about 10,000 feet in the Mediterranean Sea." She adds that the cockpit voice recorder is still being repaired in Paris.

The investigators also say that some of the recovered wreckage from the front of the plane "showed signs of high temperature damage and soot." They say they are working to "try to identify the source and reason for those signs."

The search continues for remains of the passengers. As we have reported, the plane disappeared from radar over the Mediterranean while flying at an altitude of 37,000 feet.

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