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The reports could not immediately be confirmed by NBC News, but Malaysia Airlines said on its Twitter account that it had lost contact with an aircraft, Flight 17 from Amsterdam to Kuala Lumpur. A Reuters correspondent in eastern Ukraine reported seeing the burning wreckage of a plane and bodies on the ground.
More than four months ago, Malaysia Airlines Flight 370, flying from Kuala Lumpur to Beijing with 239 people on board, disappeared in the greatest mystery in modern aviation. Multi-nation
have turned up no sign of that aircraft.
The Interfax report said that the crash Thursday was in eastern Ukraine, which is been among the most volatile regions in the world. Pro-Russian separatists have been fighting Ukrainian security forces there for months.
In the chaotic early hours after the plane went down, the separatists and the Ukrainian government each said the other had shot it down.
A Ukrainian interior ministry official said that pro-Russian separatists had downed the plane, and a leader of the separatists, Aleksander Borodai, said that it was the Ukrainian air force.
Malaysian Prime Minister Najib Razak said on Twitter: “I am shocked by reports that an MH plane crashed. We are launching an immediate investigation.”
The defense minister, Hishammuddin Hussein, said that there was no confirmation that the plane had been shot down. He said on Twitter that the Malaysian military had been instructed to “get on it.”
President Barack Obama was briefed and directed his team to be in close touch with senior Ukrainian officials, press secretary Josh Earnest said. Officials at the Pentagon scrambled to learn more and assess who might have had the capability to shoot down an airliner.
The conflict in Ukraine has raised tensions between Russia and the West to their highest since the end of the Cold War.
In February, protesters toppled the pro-Russian government in Kiev, and Russia answered by invading and later annexing the Crimean peninsula of Ukraine. Since then, pro-Russian separatists have fought Ukrainian security forces in the east.
Evan Kohlmann, an NBC News terrorism analyst, said that shooting down a 777 at 33,000 feet would require “access to serious military equipment.”
“The chances this was done by a conventional terrorist group like al Qaeda or something like that is almost nonexistent,” he said.
A Ukrainian military cargo plane was shot down earlier this week, but it was not clear who shot it down.
The FlightStats website showed the last recorded position of Flight 17 over Ukraine, west of the Russia border, at about 9:20 a.m.
American commercial airliners have been prohibited from flying over some parts of Ukraine since April, after Russian President Vladimir Putin moved to annex Crimea.
Boeing said it was trying to learn more and that its thoughts and prayers were with everyone on board, their families and loved ones.
The Boeing 777 had one of the best safety records in the industry. In July 2013, a 777 operated by Asiana Airlines crash-landed in San Francisco. Flight 370, which was also a 777, disappeared March 8.