Fire engines arrive at the crash site of a passenger jet near the village of Grabovo, Ukraine. The craft carried 295 people. / Dmitry Lovetsky, AP
WASHINGTON â?? The crash of a Malaysian Airlines passenger aircraft over Ukraine on Thursday followed reports that two Ukrainian military aircraft were shot down earlier this week and that Russians have been building up forces along the border.
The crash comes amid an escalating conflict in Ukraine and accusations by Washington that Russia is supplying rebels with sophisticated weapons and equipment.
The U.S. and Ukrainian governments say a missile strike took down the plane, but they have not identified the source.
A Ukrainian military cargo plane and a fighter jet crashed this week in separate incidents as Ukrainian forces clashed with Russian-backed separatists, raising concerns that separatists may be armed with sophisticated anti-aircraft weapons.
The cargo plane, an Antonov 26, appears to have been shot down by a surface-to-air missile Monday, according to a senior Obama administration official interviewed Wednesday. Two senior Defense officials made a similar assessment Thursday. They did not want to be identified by name because they are not authorized to discuss those details publicly.
Two crew members died and six parachuted to safety, according to the Ukrainian government.
A Russian combat aircraft shot down an Su-25 fighter on Wednesday, Andriy Lysenko, a spokesman for Ukraine's National Security and Defense Council, said Thursday. U.S. officials had not made an assessment on how it was downed.
Military and administration officials suspect the cargo plane was shot down by a surface-to-air missile at an altitude of 21,000 feet. Only sophisticated weapons systems could reach that height, the senior administration official said.
The capabilities of such systems are greater than those of portable missiles, such as Stingers, which have a much shorter range.
Surface-to-air missile systems are much larger and generally are tied into radar networks. They are operated by crews of 15 to 20 people.
Pentagon spokesman Steve Warren said up to 10,000 Russian troops are massed along Russia's border with Ukraine.
The Pentagon hasn't identified surface-to-air missiles, but it has said Russia supplies rebels with artillery, small arms and other weapons.
The Malaysia Airlines jet that crashed over Ukraine on Thursday was well within the range of missiles used by the separatist rebels, according to Richard Lloyd, a warhead designer who consults for Tesla Laboratories in Arlington, Va.
The Boeing 777 was traveling from Amsterdam to Malaysia's capital, Kuala Lumpur, with 295 people aboard when Ukrainian air traffic control lost contact with it. The plane carried 280 passengers and 15 crew.
An adviser to Ukraine's interior ministry said rebels struck the plane with a missile, most likely from the Buk weapon systems, a self-propelled medium-range missile.
"Quite frankly, they have a very long reach," Lloyd said. "A warhead like this would be pretty catastrophic against an airliner.'
The State Department issued a statement Monday accusing Russia of arming the rebels.
"We assess that Russia continues to provide them with heavy weapons, other military equipment and financing, and continues to allow militants to enter Ukraine freely," it said.
The former Soviet Union and Russia developed the Buk missile system.
It can carry a large 140-pound warhead, Lloyd said. By comparison, a Patriot missile has a 180-pound warhead.
A Buk-launched missile can travel about 46,000 feet, well within the range of the flight path of a commercial aircraft, Lloyd said.
Commercial jets are considered soft targets. Unlike a military craft, such jets do not have reinforcements to protect their most vulnerable areas or detection systems that would allow the plane to take a countermeasure to avoid a missile hit.
"In general, the aircraft are not designed for these types of things," Lloyd said.
Copyright 2014USA TODAY
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