For a month the two men could not tell their psychologist what had happened to them, only that it was horrible beyond words. “If there’s hell somewhere, it’s worse than that,” said one.

The Ukrainian soldiers, aged 25 and 28, had been in Russian captivity — one for one month, the other for three.

After their return in a prisoner swap they had been referred to Anzhelika Yatsenko, 41, a psychologist in Poltava who deals with troubled young men. They were suicidal. The younger one had tried to kill himself. “I knew from previous cases they had probably been tortured,” she said. “As someone who gets referred the hardest cases, mostly men under 35, it’s very hard to surprise me.”

When they finally told her, it was, she said, “the first time I behaved not like a professional psychologist”. “I’d never heard anything so horrible. I told them I needed the bathroom and went and cried and cried. I didn’t want them to see as they might think there’s no hope.” The two men had been savagely beaten. Then the drunken Russians castrated them with a knife. “One of them told me, ‘I don’t know how I am still alive, there was so much blood, I thought I’d die of blood poisoning’,” she said. “And of course it’s not just the physical damage. Imagine, they are young men just starting their sexual life and then in one second it’s all over. They still feel something, all these hormones, but they can’t do anything. They can never be sexually active. For a young man it’s the worst thing to happen. “Their dignity has been damaged so badly and it’s impossible to forget. The Russians told them, ‘We are doing this so you can’t have kids.’ To me this is genocide.” Their treatment illustrates the heavy cost of this brutal war — one that is only likely to rise as Ukrainian forces try to breach Russian lines in the early stages of their counteroffensive. Using new western kit, including German Leopard tanks, Bradley fighting vehicles from the US and Storm Shadow cruise missiles from the UK, the Ukrainians have been trying to punch their way through parts of the 600-mile front line from Donbas in the east to Zaporizhzhia region in the south, where they hope to cut off Russia’s land bridge to Crimea.

There have been many reports of Ukrainians insisting on returning to battle even after losing arms and legs. Astonishingly, among those fighting is the older of the two castrated men whom Yatsenko has been counselling. “He insisted on rejoining,” she said shaking her head. “He says he’s needed and it’s easier being in a place where there are no women. I guess, given what happened, he wants to kill Russians.”

She has another fear, however. “He may feel his life is worth nothing and just wants to die.” Thousands of soldiers on both sides have been taken prisoner in the 16 months since the Russian invasion. Kyiv does not release figures but there have been periodic prisoner swaps such as that which saw the return of these two men. Last Monday President Zelensky posted a video to greet the return of 95 prisoners, noting 2,526 had been returned so far. “We remember everyone, we are searching for each and every one of them, and we have to bring them all back,” he said. “And we will.” Yatsenko believes her patients are not the only ones to have been castrated. “They told me the Russians performed the castration procedure very skilfully, as if they knew how to do it. And I’ve heard about a lot of cases from colleagues treating others.”

Last July a sickening video emerged, posted on pro-Russian Telegram channels, that appeared to show a Russian soldier castrating a Ukrainian prisoner. The soldier, wearing the distinctive Russian Z patch, is wearing blue surgical gloves and holding a green box-cutter knife as he reaches down on a prisoner lying face down with his hands tied, his mouth gagged and the back of his trousers cut away. The prisoner is wearing Ukrainian camouflage. A second video appears to show the same prisoner shot, his testicles stuffed in his mouth.

“All the world needs to understand: Russia is a country of cannibals who enjoy torture and murder,” tweeted Mykhailo Podolyak, an adviser to Zelensky. “But the fog of war will not help Russian executioners avoid punishment. We identify everyone. We will get everyone.” Whether or not the perpetrators are tracked down, their victims’ lives have been irrevocably changed.

While there has been widespread international outrage and help for women and girls raped by Russians in occupied territories, there has been far less attention to sexual violence against men and boys, whether under occupation or in captivity. Yatsenko said the men were hard to treat. “They take a lot of antidepressants, that’s all. And we try to find some distractions for them. They can’t talk to their families or friends. “The younger one who tried to commit suicide had a girlfriend who told him she accepted him as he was but it was too hard for him to stay with her so they are now apart.” Last week she said he had stopped speaking.

“The other one had a girl he liked and planned to ask out but now cannot tell her. It’s all just so sad,” she said, “I will never forget. “On one hand I feel rage, on the other it’s pain. When I watch videos of our Ukrainian soldiers I’m so proud of them, but then I hear these stories.” Like many Ukrainians, Yatsenko has close links with Russia. Her father is Russian and she lived there, in Rostov, until she was 18, when she moved to Ukraine to study and never went back. They are no longer in touch. “This thirst for violence is in Russians’ blood,” she said. “I saw it growing up. They always hated us Ukrainians, abused our women as prostitutes. When I said I was going to study in Poltava, they laughed at me. “They can’t beat us on the battlefield, the whole world is helping us, so they do this — to demoralise us, to spread fear, to have this small revenge. It’s like blowing up the [Kakhovka] dam [on June 6], they can’t have Kherson so they destroy it.”

Doctors at the maternity hospital in Poltava said they had been consulted about women from occupied areas who had been raped by Russians then had their vaginas injected with window sealant so they can never have children. Yatsenko shook her head. “I have a client from Georgia and she was tortured by Russians during the war there [in 2008] and fled to Ukraine. When war started here, she immediately took her kids and left, telling me, ‘I know what they are doing with young girls.’ I didn’t understand then, but now I do.”

Since the counteroffensive began last week, the Ukrainians have liberated a handful of villages in farming hinterland of eastern Donetsk just south of the frontline town of Velyka Novosilka, and about 80 miles north of the decimated Russian-occupied city of Mariupol. Although these victories have enabled them to post morale-boosting videos of troops waving flags, these are tiny places and this is incremental progress, less than a mile, at what appears to be a heavy cost. Moscow has posted images of destroyed Ukrainian tanks and Bradley fighting vehicles and claims to have taken many Ukrainian lives. Ukraine says it has killed more troops than it has lost but conceded that there was “extremely fierce fighting” in the Zaporizhizhia and Donetsk regions as troops inched south, and according to western officials is taking “significant casualties”. Access for the media has been tightly restricted. The Ukrainian defence ministry is sticking to the line “plans love silence” and citing operational security, making it hard to get a clear picture. On Thursday, we visited part of the liberated area with the American billionaire philanthropist Howard Buffett — son of Warren — and one of the organisations he funds, the Global Empowerment Mission (GEM) set up by the Miami businessman Michael Capponi, taking in the first aid since liberation. Ukraine’s control appeared tenuous. Though most of the noise was outgoing fire from pounding Ukrainian howitzers, there had been airstrikes the previous day on Velyka Novosilka.

The once bustling town of 50,000 has less than 5,000 mostly elderly people who do not want to leave. One group of 49 had been living for more than a year in the basement of a school which has been extensively shelled, its roof blown off. Iryna Babkina, 46, the music teacher, who the others describe as their mayor, gave us a tour of their damp-smelling underground accommodation, including beds, tables and chairs, sacks of potatoes, a stove and a fish tank with four miniature goldfish. Outside dogs and cats ran around. “There are explosions all the time but we know our forces are pushing Russians back so we will stay here to victory,” said Katerina Subert, 68, who before the war worked as a cook in the local food-canning factory. “It’s not much of a life but we have got used to it.” A planned trip on to recently freed Neskuchne had to be abandoned because of shelling and we bumped along country lanes to Zolota Nyva, a hamlet liberated earlier where villagers appeared in tears to see outsiders with boxes of basics such as flour, sunflower oil, toilet paper and toothpaste. “This is the first aid we have been brought,” said Tanya Silivonits, 38. “It was so hard under the Russians, we just lived on what we could grow.” Even there, we were forced to make a hasty exit as two Russian drones appeared overhead. Just after we drove back through Velyka Novosilka the town was shelled again. “It’s difficult. We’re only getting two or three hours sleep,” said Pavlo, the commander of one artillery brigade providing cover for infantry advancing on Marinka, 30 miles to the east. “But bit by bit we’re pushing forward and they are retreating and today was a good day.”

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