A total of 196 bodies have been recovered so far from the Malaysia Airlines crash site.
However, armed rebels loaded all the 196 bodies onto refrigerated train bound for a rebel-held city, Ukrainian officials and monitors said.
Ukraine and the separatists accuse each other of firing a surface-to-air missile at Malaysia Airlines Flight 17 on Thursday.
All those on board the flight – 283 passengers and 15 crew – were killed.
Ukraine says Russia has been sending sophisticated arms to the rebels, a charge that Moscow denies.
The US embassy in Kiev issued a strong statement pointing to Russian complicity in arming the rebels, AP reported.
The rebels have been strictly limiting the movements of international monitors and journalists at the crash site, which is near the Russian border, and Ukraine's Emergency Ministry said its workers were labouring under duress, overseen by the armed rebels.
