Reuters reported that one of its correspondents in Eastern Ukraine saw the burning wreckage of an airplane, with bodies on the ground.
The airliner was shot down at an altitude of 10 kilometres above eastern Ukraine, the Ukrainian bureau of the Russian-based news agency Interfax reported.
Malaysia Airlines tweeted that it has lost contact with Flight MH17 and that the last known contact with the aircraft was over Amsterdam. The Boeing plane was flying from Amsterdam to Kuala Lumpur.
The flight tracking websiteFlight Aware shows an aborted flight path for Flight MH17 that ends over western Ukraine near the border with Poland.
The Associated Press reported that Anton Gerashenko, an adviser to Ukraine's interior minister, said on his Facebook page the plane was flying at an altitude of 10,000 metres when it was hit Thursday by a missile fired from a Buk launcher.
Ukrainian Prime Minister Areseny Yatseniuk has ordered an investigation into the "airplane catastrophe" in Eastern Ukraine, his spokeswoman Olga Lappo said on Thursday, Reuters reported.
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