LATEST: U.S. and European government sources close to the probe say investigators are skeptical over a theory that the missing aircraft was the target of an attack.
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- EXCLUSIVE - Malaysia plane probe narrows on mid-air disintegration - source
Malaysia Airlines flight MH370 vanished after climbing to a cruising altitude of 35,000 feet between Kuala Lumpur and Beijing in the early hours of Saturday. "The fact that we are unable to find any debris so far appears to indicate that the aircraft is likely to have disintegrated at around 35,000 feet," said the source, who is involved in the preliminary investigations in Malaysia.