Allegations of brutal interrogations, where Ukrainian men were shot and threatened with rape, have been made by a former Russian military officer.
Konstantin Yefremov, the most senior officer to speak openly, told the BBC in an exclusive interview Russia now sees him as a traitor and defector.
At one site in southern Ukraine, he said “the interrogations, the torture, continued for about a week”.
Mr Yefremov tried to resign from the army numerous times – but he ended up being dismissed for refusing to return to Ukraine. He has now fled Russia
