A review of imagery from U.S. government satellites has so far produced no heat signature or indication of an explosion along the plane’s flight path, officials said. U.S. officials now want to review the satellite images taken by other nations and private companies to see if they might offer a better view.
Nevertheless, some U.S. officials wonder whether the plane’s reported turns and apparent rapid descent suggest an explosion brought it down.
“It doesn’t look good,” one official said, noting the lack of a mayday call and no known mechanical issues with the plane.
But “we don’t have any forensic evidence from the plane yet,” another official said. And without forensic evidence, it’s just “too early to tell” what happened, according to a third official.
The possibility of pilot suicide or another deliberate act by a pilot must also be considered, sources said.
Meanwhile, the U.S. government is undertaking an intensive background investigation of the pilots and crew, and the names of passengers on the manifest are being run against all U.S. and western terror watch-lists, officials said.
U.S. intelligence agencies are also poring over information to see if radicals using known channels and websites have been boasting about the attack.
So far no credible claims of responsibility have been received.
ABC News' Mike Levine contributed to this report.