President Obama said Friday that at least one U.S. citizen was on the Malaysia Airlines jet shot down over separatist-controlled eastern Ukraine on Thursday, killing all 298 aboard.
"A surface-to-air missile was fired, and that's what brought the jet down," he said. "That shot was taken in a territory controlled by the Russian separatists."
Obama said the separatists had received a steady flow of support from Russia, including arms and heavy-weapons training.
Personnel and investigators from the FBI and the National Transportation Safety Board are headed to Ukraine, he said.
"This was a global tragedy," Obama said in his address.
Obama said the incident should "snap everybody's heads to attention" that the conflict in Ukraine has consequences across the region.
"It is not going to be localized, it is not going to be contained," he said.
Obama said he did not see a U.S. military role beyond support for NATO.
U.S. intelligence sources told The Times that tracking data from spy satellites and radar confirmed that the Boeing 777 en route from Amsterdam to Kuala Lumpur, Malaysia, was hit by a missile in midair Thursday.
On Friday, a U.S. official said American intelligence agencies had reached a preliminary conclusion that pro-Russia separatists in Ukraine fired the missile that brought down the airliner.
The U.S. is seeking further intelligence before reaching a final conclusion, the official said.
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