(CNN) -- Investigators probing the June crash of an Air France flight in the Atlantic Ocean still do not know what brought the plane down, who was at the controls when it crashed, or what the pilots did in the moments leading up to the disaster, according to a new report released Thursday. "At this stage ... it is still not possible to understand the causes and circumstances of the accident," investigators said in the report. Flight 447 -- an Airbus A330 -- went down in stormy weather in the Atlantic Ocean June 1 while flying from Rio de Janeiro, Brazil, to Charles de Gaulle Airport in Paris, France. All 228 people on board were killed. Most of the bodies were never recovered.
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Investigators still don't know what caused an Air France jet to crash
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The flight data recorder and cockpit voice recorder have never been found
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Investigators are preparing to begin a new search for the recorders in February
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Flight 447 went down in stormy weather in the Atlantic Ocean on June 1, 2009
Before it crashed, @placeholder sent out 24 automated error messages that suggested the plane may have been flying too fast or too slow through the thunderstorms, officials have said.