Data evidence from Malaysia Airlines flight MH17 showed it crashed after it was hit by shrapnel from a missile, according to Ukraine's National Security and Defense Council.
Colonel Andriy Lysenko, spokesman for the Council, said an analysis of the Boeing 777 black boxes showed the aircraft experienced "massive explosive decompression" after it was punctured multiple times by fragments he said came from a missile.
The black boxes are currently being examined by British aviation experts.
The West claims the passenger jet was downed by pro-Russian rebels in eastern Ukraine with a sophisticated surface-to-air missile system supplied by Moscow.
The Kremlin and the insurgents deny that and have voiced various conspiracy theories, including the possibility the plane was blown out of the sky by a Ukrainian fighter jet that mistook it for Russian President Vladimir Putin's aircraft.
Navi Pillay, the UN High Commissioner for Human Rights, said the downing of MH17 might constitute a war crime.
"This violation of international law, given the prevailing circumstances, may amount to a war crime," she said.
Meanwhile, an international police team abandoned its attempt to reach the crash site for a second day running due to fighting in the area.
An Australian and Dutch security team was due to get to the site lying in a rebel-held area and secure it to allow the launch of comprehensive investigations into the crash.
But fierce fighting between government troops and the rebels have left the team stranded some 20 miles (30km) away in the town of Shakhtarsk.