Satellite images show destruction of Olenivka prison.

New satellite images, released by Maxar Technologies, show Olenivka prison camp in Donetsk Oblast before and after the explosion or attack that killed at least 50 captive Ukrainian soldiers. The images show that only one section of the prison was destroyed, with no visible damage anywhere around it, including to adjacent buildings.

Ukraine said that, days before the July 28 attack, Russians singled out Ukrainian members of the well-known Azov Regiment, who were captured in Mariupol and were awaiting a prisoner exchange, to the separate part of the prison building – the one that was destroyed.

Ukrainian authorities said that Russia either hit the prison with artillery or blew it up from inside. Russia accused Ukraine of attacking the prison with HIMARS, a high-precision rocket system. The prison is in the part of eastern Ukraine that has been occupied by Russia since 2014, and is under control of Russia's proxies.

Following the attack, a senior Pentagon official warned against trusting Russia's version of events.

"I would ask, you know, as you all look at this, that we apply some caution specifically to what the Russians are telling us, just because we know that they have made several claims in the past that have not been close to correct,” a senior defense official said at a background briefing, the transcript of which was published by the U.S. Department of Defense.

Russia said it will allow United Nations and the International Committee of the Red Cross experts at the site in Olenivka. Previously the Ukrainian government called on the UN and ICRC to investigate the attack.