The body of a British aid worker who was captured by Russian proxies in April has been handed to Ukraine with “possible signs of unspeakable torture”, according to the country’s foreign minister, Dmytro Kuleba. Paul Urey, 45, from Warrington, Cheshire, was captured in April by pro-Russian separatists, along with another Briton, Dylan Healey. The two men were later charged with “mercenary activities” by the self-proclaimed Donetsk People’s Republic (DNR), but in July the Russian proxy authorities announced that Urey had died as a result of “illness and stress”. Late on Wednesday Kuleba wrote on Twitter that Urey’s body had been returned, showing possible signs of torture. “Detaining and torturing civilians is barbarianism,” he posted. “I express my deepest condolences to relatives and close ones of Paul Urie [sic]. He was a brave man who dedicated himself to saving people.” “Ukraine will never forget him and his deeds. We will identify perpetrators of this crime and hold them to account. They won’t escape justice.” Urey and Healey, both described as independent aid workers, were captured at a checkpoint while driving to help a woman and two children, according to the non-profit Presdium Network, who were operating in Ukraine but did not employ the pair. In early May, a handcuffed Urey appeared on Russian state television criticising the British government and criticised British media coverage of the Russia’s invasion. The following month, Daria Morozova, a representative for the Donetsk occupying authorities, announced Urey’s death. Urey’s mother, Linda, had previously said that her son had type 1 diabetes, which requires daily insulin. Upon hearing of her son’s death, she wrote on Facebook that she had told them “he was a very sick man”. She said she was very angry, asking, “Why did you let him die? I want answers. Why didn’t you release him? “I hate you all. I’m absolutely fuming, I really am … Murderers, that’s what you are.” The Foreign Office summoned Andrei Kelin, Russia’s ambassador to the UK, after Urey’s death. The then foreign secretary, Liz Truss, said she was “shocked” by reports of Urey’s death and that Russia “must bear the full responsibility”. Healy, and four other foreigners captured in eastern Ukraine, have pleaded not guilty to charges of being mercenaries and “undergoing training to seize power by force”. They could face the death penalty. The next court hearing in their case is set for October, according to Russia’s RIA Novosti.