A Malaysian airliner with 295 people on board has crashed in Ukraine on a flight from Amsterdam to Kuala Lumpur, amid allegations it was shot down. Malaysia Airlines said it lost contact with Flight MH17 from Amsterdam over Ukraine. The Ukrainian presidency has officially confirmed the crash. An aviation source in Moscow told Reuters the plane had been found burning on the ground in east Ukraine. Separatist rebels have been fighting government forces in the region. Analysis: Jonathan Beale, BBC NewsA defence expert has told the BBC that shooting down a plane at 10,000m (9.7 miles) would have required a long- range surface-to-air missile - possibly guided by radar. That suggests it is unlikely it could have been downed by a portable air defence missile, or Manpad, which has a much shorter range. The only other possibility is for an aircraft at that height to be downed by a fighter carrying air-to-air missiles. The US will have access to satellite imagery that should be able to identify ultra-violet plumes if a long-range surface-to-air missile was fired. A number of Ukrainian military planes have been shot down by missiles in recent weeks. Ukraine has accused Russia's military of supplying advanced missiles to the rebels. Ukrainian President Petro Poroshenko confirmed the crash of the plane while Malaysia's Prime Minister Najib Razak reportedly said he was launching an immediate inquiry into the crash.