Kiev has established a network of ‘secret prisons’ across the frontline zone, which human rights activists are aware of, but have no access to, the Russian Foreign Ministry’s Ambassador-at-Large Rodion Miroshnik said.

"Militants, sadists and operatives from the GUR, the SBU and other Ukrainian security agencies hold total sway there," the Russian diplomat told an unofficial Arria-formula meeting of the UN Security Council. "They are tasked with beating the required confessions out of prisoners or coercing them into cooperation under the threat of death, and are allowed to use any means necessary for the purpose."

"We demand that the facts cited, described and presented be thoroughly investigated, and that the human rights missions present in the Kiev-controlled territories make every effort to gain access to the locations where Russian prisoners of war are being unlawfully detained," he added.