Ukrainian officials say they've been told the downed Malaysian airliner's black boxes suggest the plane's fuselage was punctured by shrapnel from a missile.
At the same time, heavy fighting in eastern Ukraine is hampering the international investigation into the crash.
CRI's Qi Zhi has more.
The flight data recorders of Flight MH17 are being analyzed in Britain by British experts.
Andriy Lysenko, Ukraine's security spokesperson, says initial analysis suggests the plane suffered a massive, explosive loss of pressure after it was hit by fragments believed to have come from a missile.
"The experts who are investigating the reasons behind the Boeing 777 crash informed us that data from the recovered flight data recorders shows that the reason for the sudden falling and the crash was because of a massive, explosive loss of pressure after being punctured multiple times by shrapnel."
But it remains unclear who fired a missile, with the Ukrainian rebels and Kiev blaming each other.
Dutch investigators leading the investigation have refused to comment on the new Ukrainian suggestion.
On the ground, heavy fighting is preventing an international delegation of Australian and Dutch police and forensic experts from reaching the crash site for a second consecutive day.
Alexander Hug is the deputy chief of the OSCE Special Monitoring Mission to Ukraine.
"We returned prematurely from a trip to the site. We were stopped in the town of Shakhtarsk on the way to the crash site. We were stopped because there was gunfire and, what we understand was, artillery impacts nearby, very near. We are sick and tired of being interrupted by gunfights, despite the fact that we have agreed that there should be a ceasefire."
The Ukrainian military says it has managed to capture two towns near the wreckage in its bid to win back the territory from the hands of the rebels.
Kiev is also accusing the separatists of continuing to interfere with the wreckage of the plane.
Ukraine's foreign minister says creating a ceasefire in the area of the crash site remains a priority.
In another development, the United Nations High Commissioner for Human Rights, Navi Pillay, says the downing of Flight MH17 could constitute a war crime.
As such, she's demanding a prompt, independent, impartial investigation into exactly what brought the plane down, leaving 298 people dead.
For CRI, I'm Qi Zhi.
