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Watch: "I apologise to the whole Ukrainian nation" – former Russian army officer
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".
"Every day, at night, sometimes twice a day."
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.
Using photographs and military documents supplied by Mr Yefremov, the BBC has verified he was in Ukraine early in the war – in the Zaporizhzhia region, including the city of Melitopol.
This article contains graphic descriptions of torture.
Konstantin Yefremov's face flickers into view on my computer screen and we start to talk. He is a man with a story to tell. Until recently he was a Russian army officer.
Deployed to Ukraine last year, the former senior lieutenant has agreed to tell me about the crimes he says he witnessed there – including torture and mistreatment of Ukrainian prisoners. He will talk about his comrades looting occupied areas of Ukraine, and describe brutal interrogation sessions, led by a Russian colonel, in which men were shot and threatened with rape.
On 10 February 2022, Mr Yefremov says he arrived in Crimea, the Ukrainian peninsula annexed by Russia nine years ago. He was the head of a de-mining unit of the 42nd Motorised Rifle Division – and was usually based in Chechnya, in Russia's North Caucasus. He and his men were sent to take part in "military exercises", he says.
"At the time no-one believed there would be war. Everyone thought this was only a drill. I'm sure even senior officers didn't know."
Mr Yefremov recalls seeing Russian troops taping identification marks on their uniforms and painting the letter "Z" on military equipment and vehicles. Within days, "Z" had become the symbol of what the Kremlin was calling its "special military operation".
Mr Yefremov claims he wanted nothing to do with it.
"I decided to quit. I went to my commander and explained my position. He took me to a senior officer who called me a traitor and a coward.
"I left my gun, got in a taxi and drove off. I wanted to return to my base in Chechnya and resign officially. Then my comrades telephoned me with a warning.
"A colonel had promised to put me in prison for up to 10 years for desertion and he'd alerted the police."
Mr Yefremov says he called a military lawyer, who advised him to turn around.
"I realise now I should have ignored that and driven on," he says. "But I was afraid of being put in jail."
He went back to join his men.
Mr Yefremov insists he is "anti-war". He assures me he did not participate in Russia's annexation of Crimea, or fight in eastern Ukraine when war first erupted in the Donbas nine years ago.
In 2014, Russia was not only accused of orchestrating a separatist uprising there, but of sending in its own troops. Konstantin also tells me he has not taken part in Russia's military operation in Syria.
"For the last three years I had been involved in mine clearance in Chechnya, a place that had experienced two wars. I think the work I've done there has benefited people."
Mr Yefremov was placed in temporary charge of a rifle platoon. On 27 February, three days after the Russian invasion, he says he and his men were ordered to move north from occupied Crimea. They headed for the city of Melitopol.
The next 10 days were spent at an airfield which had already been captured by Russian troops. He describes the looting he witnessed.
"Soldiers and officers grabbed everything they could. They climbed all over the planes and went through all the buildings. One soldier took away a lawnmower. He said proudly, 'I'll take this home and cut the grass next to our barracks.'
"Buckets, axes, bicycles, they bunged it all in their trucks. So much stuff they had to squat down to fit in the vehicles."
Mr Yefremov has sent us photographs he says he took at Melitopol air base. They show transport planes and a building on fire.
They are among a number of pictures and documents he has shared – and which we have verified – to confirm Mr Yefremov's identity, rank and his movements in Ukraine in the spring of 2022.
Online mapping tools confirmed the images of Melitopol air base.
For a month and a half, he and eight soldiers under his command guarded a Russian artillery unit there.
"The whole time we slept outside," he recalls. "We were so hungry we started hunting for rabbits and pheasants. One time we came across a mansion. There was a Russian fighter inside. 'We're with the 100th Brigade and we live here now,' the soldier said.
"There was so much food. The fridges were packed. There was enough food to survive a nuclear war. But the soldiers living there were catching the Japanese carp in the pond outside and eating them."
Konstantin Yefremov's group moved to guard what he describes as a "logistics headquarters" in April – in the town of Bilmak, to the north-east of Melitopol. There, he says he witnessed interrogations and mistreatment of Ukrainian prisoners.
He recalls a day when three prisoners were brought in.
"One of them admitted to being a sniper. On hearing this, the Russian colonel lost his mind. He hit him, he pulled the Ukrainian's trousers down and asked if he was married.
"'Yes,' the prisoner replied. 'Then someone bring me a mop,' said the colonel. 'We'll turn you into a girl and send your wife the video.'"
Another time, says Mr Yefremov, the colonel asked the prisoner to name all the Ukrainian nationalists in his unit.
"The Ukrainian didn't understand the question. He replied that the soldiers were naval infantry of the Ukrainian armed forces. For that answer they knocked out some of his teeth."
The Kremlin wants Russians to believe that, in Ukraine, Russia is fighting fascists, neo-Nazis and ultra-nationalists. This false narrative serves to dehumanise Ukrainians in the eyes of the Russian public and the military.
Mr Yefremov says the Ukrainian prisoner had a blindfold on.
"The colonel put a pistol to the prisoner's forehead and said 'I'm going to count to three and then shoot you in the head.'
"He counted and then fired just to the side of his head, on both sides. The colonel started shouting at him. I said: 'Comrade colonel! He can't hear you, you've deafened him!'"
Mr Yefremov describes how the colonel gave orders that the Ukrainians shouldn't be given normal food – only water and crackers. But he says: "We tried to give them hot tea and cigarettes."
So that the prisoners didn't sleep on bare ground, Mr Yefremov also recalls how his men tossed them hay – "at night, so that no-one saw us".
During another interrogation, Mr Yefremov says the colonel shot a prisoner in the arm – and in the right leg under the knee, which hit the bone. Konstantin says his men bandaged the prisoner up and went to the Russian commanders – "not to the Colonel, he was crazy" – and said the prisoner needed to go to hospital, otherwise he would die from blood loss.
"We dressed him up in a Russian uniform and took him to hospital. We told him: 'Don't say you're a Ukrainian prisoner of war, because either the doctors will refuse to treat you, or the injured Russian soldiers will hear and shoot you and we won't be able to stop them."
The UN's Human Rights Office has been documenting cases of mistreatment of prisoners in the war in Ukraine. It has interviewed more than 400 POWs – both Ukrainians and Russians.
"Unfortunately, we've found there is torture and ill-treatment of prisoners of war happening on both sides," says Matilda Bogner, head of the UN's Ukraine-based monitoring team.
"If we compare the violations, the torture or ill-treatment of Ukrainian prisoners of war tends to happen at almost every stage of confinement. And, for the most part, the conditions of internment are worse in many areas of Russia or occupied Ukraine."
The worst forms of torture or ill treatment for Ukrainian prisoners of war usually occur during interrogation, says Ms Bogner. They can be subjected to electrocution and a whole range of torture methods – she says – including hanging people up and beating them.
"When they arrive at places of internment there are often so-called welcoming beatings. They also often face inadequate food and water," she adds.
Russian prisoners of war, too, have reported beatings and suffering electrocution.
"Any form of torture or ill treatment is prohibited under international law," says Ms Bogner. "It is unacceptable for either side to do this."
The BBC was unable to independently confirm Konstantin Yefremov's specific allegations of torture, but they are consistent with other claims of abuse of Ukrainian prisoners.
Russia's Defence Ministry did not immediately respond to a request for comment.
Mr Yefremov would eventually return to his de-mining unit, but not for long.
"Seven of us had taken the decision [to leave the army]," he tells me.
At the end of May, back in Chechnya, he wrote his letter of resignation. Some senior officers were not happy.
"They started threatening me. Officers who hadn't spent a day in Ukraine were telling me that I was a coward and a traitor. They wouldn't allow me to resign. I was dismissed."
Mr Yefremov shows us letters from the military.
In the first document, he is accused of "shirking his duties" and disregarding an order to return to Ukraine. It is described as "a serious breach of discipline".
The second letter refers to Mr Yefremov's "early dismissal from military service… for breaking his contract".
"After 10 years of service I was denounced as a traitor, a defector, just because I didn't want to kill people," he says. "But I was glad that I was now a free person, that I wouldn't have to kill or be killed."
Mr Yefremov was out of the army. But not out of danger of being sent back to the war.
In September 2022, President Putin declared what he called "partial mobilisation". Hundreds of thousands of Russian citizens would be drafted into the military and sent to Ukraine.
Mr Yefremov says he knew – because he had already served with the military in Ukraine – he would not be left alone. He came up with an escape plan.
"In the house where I was living I made a hatch in the attic ceiling… in case police and enlistment officers broke in to deliver call-up papers.
"Enlistment officers were driving to my house and waiting for me in their cars. So, I rented a flat and hid there.
"I hid from the neighbours, too, because I'd heard of cases when neighbours told police about young men who'd been drafted and were hiding. I found this situation humiliating and unacceptable."
Mr Yefremov contacted Russian human rights group Gulagu.net, which helped him leave Russia.
What does Mr Yefremov think about those Russians – and there are many – who express support for Vladimir Putin's decision to invade Ukraine?
"I don't know what's going on in their heads," he says. "How could they allow themselves to be fooled? When they go to market, they know they could be short-changed. They don't trust their wives, their husbands.
"But the man who has been deceiving them for 20 years, he only has to give the word and these people are ready to go and kill and die. I can't understand it."
As we end our chat, Mr Yefremov says sorry to the people of Ukraine.
"I apologise to the entire Ukrainian nation for coming to their home as an uninvited guest with a weapon in my hands.
"Thank God I didn't hurt anyone. I didn't kill anyone. Thank God I wasn't killed.
"I don't even have the moral right to ask for forgiveness from the Ukrainians. I can't forgive myself, so I can't expect them to forgive me."
Producer: Will Vernon
Open source analysis: Joshua Cheetham
With help from Gulagu.net
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