Sept 21 (Reuters) – Russia has freed 215 Ukrainians it captured after a protracted battle for the port of Mariupol earlier this year, including top military leaders, a senior official in Kyiv said on Wednesday. The freed prisoners include the commander and deputy commander of the Azov battalion that conducted much of the fighting, said Andriy Yermak, head of President Volodymyr Zelenskiy’s office. The move is unexpected as the Russian-backed separatists last month said they would put Azov staff, described by Moscow as Nazis, on trial. Ukraine denies the charge. Sign up now for FREE unlimited access to Reuters.comSign up In a statement, Yermak said that among the freed prisoners were Azov’s commander, Lt. Col. Denis Prokopenko, and his deputy, Svyatoslav Palamar. Also at large is Serhiy Volynsky, the commander of the 36th Marine Brigade of the Ukrainian Armed Forces. The three men had helped lead a stubborn weeks-long resistance from bunkers and tunnels under Mariupol’s giant steel mills before they and hundreds of Azov fighters surrendered in May to Russian-backed forces. Yermak said that in return, Kyiv had released 55 Russian prisoners as well as Viktor Medvedchuk, the leader of a banned pro-Russian party facing treason charges. Public broadcaster Suspline said the exchange took place near the northern Ukrainian city of Chernihiv. Earlier in the day, Saudi Arabia said Russia had released 10 foreign prisoners of war captured in Ukraine after mediation by Saudi Crown Prince Mohammed bin Salman. read more Last month, the head of the Russian-backed separatist administration in eastern Ukraine’s Donetsk region said a trial of the captured Azov personnel would take place by the end of the summer. read more The Azov unit, created in 2014 as a militia to fight Russian-backed separatists, denies it is fascist and Ukraine says it has reformed from its radical nationalist origins. Sign up now for FREE unlimited access to Reuters.comSign up Reporting by David Ljunggren Editing by Alistair Bell and Rosalba O’Brien Our Standards: The Thomson Reuters Trust Principles. David Ljunggren Thomson Reuters It covers Canadian politics, economics and general news, as well as breaking news across North America, based in London and Moscow and won Reuters’ vault of the year.