A picture taken on July 17, 2014 shows wreckages of the malaysian airliner carrying 295 people from Amsterdam to Kuala Lumpur after it crashed, near the town of Shaktarsk, in rebel-held east Ukraine. Pro-Russian rebels fighting central Kiev authorities claimed on Thursday that the Malaysian airline that crashed in Ukraine had been shot down by a Ukrainian jet. AFP PHOTO/DOMINIQUE FAGET (Photo credit should read DOMINIQUE FAGET/AFP/Getty Images) A picture taken on July 17, 2014 shows wreckage of the Malaysian Airliner carrying 295 people from Amsterdam to Kuala Lumpur after it crashed, near the town of Shaktarsk, in rebel-held east Ukraine. (credit: DOMINIQUE FAGET/AFP/Getty Images)

UPDATED: July 18, 2014 5:53 a.m.

KIEV, Ukraine (WNEW/AP) — A Malaysia Airlines passenger plane carrying 298 people was shot down over eastern Ukraine on Thursday as it flew over the country, and both the government and the pro-Russia separatists fighting in the region denied any responsibility for downing the plane.

An earlier tally of 295 dead was raised to include three infants in an official list of passengers released by Malaysia Airlines. The bulk of the passengers were from the Netherlands — 154 people. Next highest was 45 from Malaysia and 27 from Australia.

No American passengers have been confirmed dead. There are still 20 passengers whose nationalities have yet to be verified.

CBS News confirms the Boeing 777 was shot down by a missile as it flew at 33,000 feet over the war zone in Ukraine, but it is not clear where the missile was fired from.

Photos: Crash Scene in Ukraine

Russian President Vladimir Putin said Ukraine “bears responsibility” for the crash because the plane was brought down in the country.

“This tragedy would not have happened, if there had been peace on that land, or in any case if military operations in southeastern Ukraine had not been renewed,” Putin said in televised comments, according to Reuters.

Wreckage and bodies are spread over several miles along the flight path, CBS News correspondent Bob Orr reports. That would be consistent with the plane being ripped apart by aerodynamic forces after the aircraft was penetrated by a high explosive projectile.

As plumes of black smoke rose up near a rebel-held village of Grabovo, an Associated Press journalist counted at least 22 bodies at the wreckage site 25 miles from the Russian border.

"We offer our deep condolences to all those who lost loved ones on board." —@PressSec on #MH17: pic.twitter.com/LN4gNIXfZh — White House Archived (@ObamaWhiteHouse) July 18, 2014

A Russian news report said pro-Russia rebels intend to call a three-day cease-fire to allow for an investigation into the crash and recovery efforts.

Ukrainian President Petro Poroshenko called the downing an act of terrorism and called for an international investigation into the crash. He insisted that his forces did not shoot down the plane.

The government of Ukraine said in a statement Thursday afternoon that it has evidence that the Russian military was involved in the crash.

Anton Gerashenko, an adviser to Ukraine’s interior minister, said on his Facebook page the plane was flying at an altitude of 10,000 meters (33,000 feet). He also said it was hit by a missile fired from a Buk launcher, which can fire missiles up to an altitude of 22,000 meters (72,000 feet).

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

Malaysia Airlines confirmed that it received notification from Ukrainian aviation authorities that it had lost contact with flight MH17 at 1415 GMT some 30 kilometers (20 miles) from Tamak waypoint, approximately 50 km (30 miles) from the Russia-Ukraine border.

It said the plane had 280 passengers and 15 crew aboard a Boeing 777 that left Amsterdam at 12.15 p.m. and was to arrive at Kuala Lumpur International Airport at 6.10 a.m. Friday.

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Interfax reports that the Ukrainian Interior Ministry says that everyone on board was killed. The Interior Ministry claims that 23 Americans were killed in the crash, according to Interfax. The State Department is looking into whether Americans were on the flight.

A source told Interfax that the plane “began to drop, afterwards it was found burning on the ground on Ukrainian territory.”

Reuters reports that body parts have been scattered seven miles within the crash site, an indication that the plane came apart mid-air. A Ukrainian Emergency Ministry official told Reuters that first responders have found at least 100 bodies.

Ukrainian pro-separatists have denied responsibility for the Malaysian Airlines civilian jet crash as Ukrainian President Petro Poroshenko says his country’s military did not shoot down the plane.

UPDATE: Pro-Russian separatists and Ukrainian officials deny involvement in the crash of @MAS jetliner flight #MH17. pic.twitter.com/g66VXCcdZh — CBS Evening News (@CBSEveningNews) July 17, 2014

“We do not exclude that this plane was shot down, and we stress that the Armed Forces of Ukraine did not take action against any airborne targets,” Poroshenko stated.

Poroshenko said “we are sure that those who are guilty in this tragedy will be held responsible.”

According to Interfax, Poroshenko called it a “terrorist act.”

The Ukrainian Foreign Ministry claims in a statement obtained by CBS News that Russia is complicit, if not responsible, for the downing of the plane.

“The plane was shot down, because the Russian air defense systems was affording protection to Russian mercenaries and terrorists in this area,” the statement read.

Dmitry Peskov, spokesman for Russian President Vladimir Putin, told The Guardian that allegations that Russia was behind the crash was just sheer “stupidity.”

CBS News reports that President Barack Obama has been briefed on the crash. Obama has instructed his team to be in touch with Ukrainian authorities.

“The world is watching reports of a downed passenger jet at the Russia-Ukraine border and it looks like it might be a terrible tragedy,” Obama said during an event held in Wilmington, Del., adding that the U.S. is working on confirming if Americans were on the flight.

During a phone call with Obama Thursday morning to express his dissatisfaction to the latest economic sanctions, Russian President Vladimir Putin brought up that there were early reports of a downed Malaysian Airlines jet in Ukraine, CBS News reports.

The Federal Aviation Administration tells CBS News that the agency prohibited U.S. carriers from flying through this region.

Flight path of @MAS flight #MH17 that's reportedly been shot down by an anti-aircraft missile in Ukrainian airspace: pic.twitter.com/9Qwchz1Qee — CBS Evening News (@CBSEveningNews) July 17, 2014

It was the second time that a Malaysia Airlines plane was lost in less than six months. Malaysia Airlines Flight 370 disappeared in March while en route from Kuala Lumpur to Beijing. It has not been found, but the search has been concentrated in the Indian Ocean far west of Australia.

Malaysian Defense Minister Hishamuddin Hussein said on Twitter there’s no confirmation that Thursday’s plane was shot down. He said he has instructed the country’s military to check and get confirmation.

The Donetsk region government said Thursday’s plane crashed near a village called Grabovo, which it said is currently under the control of armed pro-Russian separatists. The region where the flight was lost has seen severe fighting between Ukrainian forces and pro-Russia separatist rebels in recent days.

A launcher similar to the Buk missile system was seen by Associated Press journalists near the eastern Ukrainian town of Snizhne, which is held by pro-Russia rebels, earlier Thursday.

On Wednesday evening, a Ukrainian fighter jet was shot down by an air-to-air missile from a Russian plane, Ukrainian authorities said Thursday, adding to what Kiev says is mounting evidence that Moscow is directly supporting the separatist insurgents in eastern Ukraine. Security Council spokesman Andrei Lysenko said the pilot of the Sukhoi-25 jet hit by the air-to-air missile was forced to bail after his jet was shot down.

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

Moscow denies Western charges that is supporting the separatists or sowing unrest in its neighbor. The Russian Defense Ministry couldn’t be reached for comment Thursday about the Ukrainian jet and Russia’s foreign ministry didn’t respond to multiple requests for comment.

Earlier this week, Ukraine said a military transport plane was shot down Monday by a missile fired from Russian territory.

The Malaysia Airlines plane is a Boeing 777-200ER, which was delivered to Malaysia Airlines on July 30, 1997, according to Flightglobal’s Ascend Online Fleets, which sells and tracks information about aircraft. It has more than 43,000 hours of flight time and 6,950 takeoffs and landings.

If the plane was shot down, it would be the fourth commercial airliner to face such a fate. The previous three were:

– April 20, 1978: Korean Airlines Flight 902, which diverted from its planned course on a flight from Paris to Seoul and strayed over the Soviet Union. After being fired upon by an interceptor aircraft, the crew made a forced landing at night on the surface of a frozen lake. Two of the 97 passengers were killed by the hostile fire.

– Sept. 1, 1983: Korean Air Lines Flight 007 shot down by at least one Soviet air-to-air missile after the 747 had strayed into Soviet airspace. All 240 passengers and 29 crew were killed.

– July 3, 1988: Iran Air Flight 655 Aircraft was shot down by a surface to air missile from the American naval vessel U.S.S. Vincennes. All 16 crew and 274 passengers were killed.

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