The International Committee of the Red Cross says it is aware of requests by Ukraine’s U.N. ambassador and others to repatriate the bodies of Russian soldiers killed in action in Ukraine but has no numbers.

Ambassador Sergiy Kyslytsya tweeted Saturday that Ukraine has appealed to the ICRC “to facilitate repatriation of thousands of bodies of Russian soldiers” killed during its invasion of Ukraine. An accompanying chart claimed 3,500 Russian troops have been killed.

Kyslytsya tweeted that parents in Russia should have a chance “to bury them with dignity.” “Don’t let (Russian President Vladimir) Putin hide scale of tragedy,” he urged.

Laetitia Courtois, ICRC’s permanent observer to the United Nations told The Associated Press Saturday night that the current security situation “is a primary concern and a limitation for our teams on the ground” and “we therefore cannot confirm numbers or other details.”

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She said “the ICRC can act as a neutral intermediary” on the return of bodies and other humanitarian issues in conflict, including clarifying the fate of missing persons, reuniting families, and advocating for the protection of detainees “within its possibilities.”