As plumes of black smoke rose up near a rebel-held village of Grabovo in eastern Ukraine, an Associated Press journalist counted at least 22 bodies at the crash site 40 kilometers (25 miles) from the Russian border.
The plane appeared to have broken up before impact and the burning wreckage — including body parts and the belongings of passengers — was scattered over a wide area
Malaysia Airlines tweeted that it lost contact with one of its flights carrying 280 passengers and 15 crew as it was traveling from Amsterdam to Kuala Lumpur over Ukrainian airspace, but did not yet confirm the crash.
Ukrainian President Petro Poroshenko called the downing an act of terrorism and called for an international investigation into the crash.
The Donetsk region government said a plane crashed Thursday near a village called Grabovo, which it said is currently under the control of the separatists. The region where the flight was lost has seen severe fighting between the two sides in recent days.
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 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).
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.
Poroshenko said his country's armed forces didn't shoot at any airborne targets.
"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," he said. "We are sure that those who are guilty in this tragedy will be held responsible."
Separatist leader Andrei Purgin told The Associated Press that he was certain that Ukrainian troops had shot the plane down but gave no explanation or proof for his statement.
Purgin said he did not know whether rebel forces owned Buk missile launchers, but said even if they did, there had no fighters capable of operating it.
Leonard reported from Kiev, Ukraine. Contributing to this report were AP Airlines Writer Scott Mayerowitz in New York; Jill Lawless and Matthew Knight in London; Laura Mills and Jim Heintz in Moscow, and Eileen Ng and Satish Cheney in Kuala Lumpur, Malaysia.
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