Russia and Ukraine have blamed each other for a rocket attack that killed dozens of Ukrainian prisoners of war in the occupied part of Donetsk region.
The office of the Prosecutor-General disclosed that about 40 people were killed in the strike and 130 injured.
Ukraine accused Russia of targeting the prison in an effort to destroy evidence of torture and killing.
“The Russian occupants pursued their criminal goals, thus, to accuse Ukraine of committing ‘war crimes’, and to hide the torture of prisoners and shootings committed there by the orders of the occupation administration and the command of the Armed Forces of the Russian Federation,” Ukraine’s General Staff said.
“The Russian enemy continues his propaganda methods of waging information warfare in order to accuse the Armed Forces of Ukraine of shelling civilian infrastructure and the population, hiding his own insidious actions.”
Ukraine’s new Prosecutor-General Andriy Kostin said he has opened a war crimes investigation into the blast. His office added that it believed around 40 people were killed in the strike and 130 were injured.
Footage broadcast on Russian state TV shows the smoking wreckage of a building, which appears to contain some human remains. The BBC cannot independently verify the footage, but analysis suggests the building was hit with an incendiary device, not regular artillery.
Daniil Bezsonov, a spokesperson for the Russian-backed separatist Donetsk People’s Republic, said the strike had been a “direct hit on a barracks holding prisoners” and the number killed might increase.
On its part, Russia’s defence ministry said the prison camp in Olenivka was hit by Ukrainian precision rockets, and also accused Ukraine of a deliberately perpetrated provocation.
Meanwhile Ukraine’s Prosecutor-General Andriy Kostin said he had opened a war crimes investigation into the blast.