There should be “clear and legal recognition of Russia as a state sponsor of terrorism”, Ukrainian President Volodmyr Zelenskyy said on Friday evening after dozens of prisoners of war were killed in an attack involving both sides have exchanged responsibility.
Calling the strike on a prison in Russian-controlled territory a “war crime”, Zelenskyy said in a late-night video address that Moscow had “proven with numerous terrorist attacks that it is the biggest source of terrorism in the world today”.
Kremlin-backed separatists in the Donetsk region said on Friday the attack on the detention center in the town of Olenivka had killed 53 prisoners of war, including some captured after the fall of Mariupol in May. They said another 75 people were injured.
Russia denied being behind the attack and instead accused Ukraine of using a US-supplied rocket system to hit the detention center near the eastern front lines.
NBC News has not been able to independently verify either party’s claims.
Ukrainian security agencies called on the United Nations and the International Committee of the Red Cross to send their representatives for an inspection mission to the site.
The ICRC said in a statement on Friday that it was seeking access and offered its support for the evacuation of the wounded, reiterating that all prisoners of war were protected by international humanitarian law, regardless of their place of residence.

European Union High Representative Joseph Borrell also condemned the Russian armed forces in a statement and accused them of breaking the law.
After months of siege at the Azovstal steel plant in the southern city of Mariupol, Ukrainian soldiers surrendered and were evacuated to Russian-occupied territory in Donetsk as prisoners, with the mediation of the UN and ICRC, who acted as guarantors of their lives.
Ukrainian security agencies accused Russia of “cynically violating” the agreement in a joint statement on Friday evening. The sudden transfer of prisoners to a new location as well as intercepted phone conversations by Ukrainians would prove Russian involvement, the statement said.
Elsewhere, Linda Thomas-Greenfield, the US ambassador to the United Nations, told the UN Security Council on Friday that Russia had “effectively set fire to the UN charter”.
Moscow was reviewing plans to completely annex Kherson, Donetsk, Luhansk and Zaporizhzhia, in blatant violation of the UN Charter and with “flagrant disregard for the principles of national sovereignty”, she said.
In the Kherson region, however, where Ukrainian forces have mounted a counteroffensive in recent weeks, the country’s military said on Saturday it had killed dozens of Russian soldiers and destroyed two ammunition depots in the area. NBC News could not independently verify this claim.
Elsewhere in eastern Ukraine, Russian rockets hit a school building in Kharkiv, the country’s second city, overnight and another attack occurred about an hour later, Mayor Ihor Terekhov said . No injuries were reported immediately.
The bus station in the city of Sloviansk was also hit, according to Mayor Vadim Lyakh. Sloviansk is near the frontline of the fighting as Russian and separatist forces attempt to take full control of the Donetsk region, which, along with Lugansk, is one of two eastern provinces that Russia has recognized as sovereign states .
In southern Ukraine, one person was killed and six others injured in a bombardment that hit a residential area in Mykolaiv, a major port city, the region’s administration said.
But in a rare public statement on Saturday, Richard Moore, the head of Britain’s foreign intelligence agency MI6, said Russia was “out of breath”.
Moore made the above remark a precedent Publish on Twitter by the British Ministry of Defence, which described the Russian government as “increasingly desperate” and as having lost thousands of troops in its invasion of Ukraine.
Associated Press contributed.
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