Officials from several countries vow to quickly determine who's behind Thursday's downing of Malaysia Airlines Flight MH-17 and the deaths of all 298 aboard.

U.S. intelligence officials confirmed that the crash was caused by a surface-to-air missile near Ukraine's border with Russia, but have yet to determine where it originated. The incident already is inflaming tensions between the two countries and escalating political rhetoric elsewhere.

It was "not an accident, it was blown out of the sky,'' said Vice President Joe Biden.

Malaysia Airlines said Ukrainian air traffic control lost contact with Flight MH17 about 30 miles from Russia. There were no distress calls as the Boeing 777, carrying 283 passengers and 15 crew, began to break apart as it fell from the sky in the world's deadliest aviation incident since 9/11.

Crash victims and body parts were strewn among burning debris up to 10 miles away. Among the dead: 154 Dutch nationals, 27 Australians, 11 Indonesians, six Brits, four Germans, four Belgians, four French, three Filipinos and a Canadian. Malaysian Air officials have so far not identified any Americans among the passengers, although they cautioned that some nationalities have still not been verified.

The crash site is in a region where tensions and fighting between Ukraine and pro-Russian militants has festered for months. After the downing of several Ukraine aircraft in recent days, accusations, blame and finger-pointing over Thursday's crash was fevered.

A Malaysia Airlines Boeing 777 en route from Amsterdam to Kuala Lumpur with 295 people aboard crashed Thursday in Ukraine near the Russian border after reportedly being hit by a missile, according to an adviser to Ukraine's interior ministry.

Ukrainian President Petro Poroshenko called the incident a terrorist act. Russian and pro-Russian separatists denied responsibility. But Ukrainian officials said they had intercepted telephone calls in which a separatist leader talked about crash with Russian military intelligence officers. Separatists initially believed they had downed a military cargo plane, according to the SBU, Ukraine's main security agency.

U.S. intelligence officials confirmed that the flight had been downed by a radar-guided missile, although they were not in agreement where it originated. It was "not an accident, it was blown out of the sky,'' said Vice President Joe Biden.

Photos of the MH17 crash:

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The crash occurred at about 12:15 local time, two hours after the flight departed Amsterdam. It's the second involving a Malaysia Air Boeing 777 this year. On March 8, Flight 370 disappeared with 239 passengers and crew aboard on a flight from Kuala Lumpur to Bejiing. Despite one of the most extensive searches in flight history, Flight 370 has yet to be found.

State Department spokesperson Jen Psaki comments on the crash of Malaysian Airlines passenger jet in eastern Ukraine. Rough Cut (no reporter narration).

Anton Gerashenko, an adviser to Ukraine's Interior Ministry, said on Facebook that Flight MH17 was at an altitude of 33,000 feet when it was hit by a missile fired from a BUK anti-aircraft missile launcher.

Typically mounted on a vehicle, the BUK can simultaneously track and strike six targets flying different directions and altitudes, according to military think tank

A similar launcher was seen by AP journalists near the eastern Ukrainian town of Snizhne earlier Thursday.

Reaction to MH17 in Kuala Lumpur:

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Russian President Vladimir Putin brought up a downed passenger jet in a phone call with President Obama Thursday morning, White House press secretary Josh Earnest said.

Earnest said Obama "has directed his team to be in close touch with senior Ukrainian officials on this matter."

In brief remarks at an appearance in Wilmington, Del., Obama called the the incident a "terrible tragedy." The U.S. will offer "any services it can" to determine what happened, Obama said.

A separatist leader in Donetsk, in eastern Ukraine, denied that rebel forces had the capability to bring down a high-altitude aircraft.

Alexander Boroday, chairman of the Council of Ministers of the self-proclaimed Republic of Donetsk, called the incident a provocation by the Ukrainian military, the Russian Interfax news agency reported.

Amsterdam reacts to MH17:

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"Self-defense forces have no air-defense, which could target transport aircraft at that height," he told Interfax.

Russia's military also says none of its military planes have been flying close to the Russia-Ukraine border Thursday, RIA Novosti reported citing an unidentified military official.

On Wednesday, a Russian military plane allegedly shot down a Ukrainian jet fighter over Ukrainian territory, forcing the pilot to eject, according to the Ukrainian National Security and Defense Council.

The pilot of the Su-25 assault aircraft was not injured and was rescued by Ukrainian military units.

Amateur video shows smoke from a Malaysian passenger plane that crashed in eastern Ukraine, killing more than 300 people onboard including 23 U.S. citizens. Deborah Gembara reports.

Pro-Russia rebels, meanwhile, claimed responsibility for strikes Wednesday on two Ukrainian Sukhoi-25 jets. The Ukrainian Defense Ministry said the second jet was hit by a portable surface-to-air missile, but added the pilot was unscathed and managed to land his plane safely.

"There have been Ukrainian helicopters and aircraft operating under the assumption of limited separatist capabilities,'' said Damon Wilson, a Russia and Ukraine expert in the administrations of George W. Bush and Bill Clinton. "They've learned quite rudely that the separatists have more advanced weapons."

Separatists have used a version of Russia's Grad rocket that the Russian military only started using in January, Wilson said, citing sources in "U.S. government circles."

President Obama extended condolences to those who lost loved ones in Thursday's Malaysia Airlines crash in Ukraine, near the Russian border.

"This is not older, former equipment but among the most recent Russian equipment used in the Russian military," said Wilson, now deputy executive vice president at the Atlantic Council, a Washington think tank.

German, British and French airlines say they are keeping flights from crossing the region.

The White House says Obama directed senior U.S. officials to remain in close touch with Ukrainian officials about downed plane Rough Cut (no reporter narration)

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FlightRadar24 tweeted an image of MH17's flight path before it disappeared from radar:

Contributing: Oren Dorell in McLean, Va., Donna Leinwand Leger in Washington, D.C., Jabeen Bhatti in Germany and the Associated Press.

Follow Doug Stanglin on Twitter: @dstanglin. follow Strauss @gstrauss_

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