A Ukrainian man has alleged he was tied up, beaten and shocked with an electric charge during Russia’s occupation of his village.
But instead of Russian soldiers abusing him directly, Andrii Matiazh, 46, alleged it was local Ukrainian policemen who had switched allegiance.
“Someone tortured me,” he said, speaking at his home in Volokhivka, which sits around four miles from Ukraine’s border with Russia.
“They used to be in the police force before the invasion and then they turned to the Russian side.”
Ukraine has accused Russian forces of using torture in the areas they controlled, saying more than 10 torture chambers have been found in newly-liberated parts of Kharkiv region, in the northeast of the country.
But Mr Matiazh’s claims help to illustrate an added challenge.
Not only must the authorities investigate suspected war crimes by Russian invaders, including torture, murder and rape, but they also need to be alert for Ukrainian collaborators.
Over the past fortnight, Ukraine’s military has recaptured towns and villages right up to the Russian border, including a number of crossing points.
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But they have yet to secure the peace, with the risk of Russian shelling at one of the border crossings deemed so great on Sunday that Sky News was told it was too dangerous to visit.
We were able, though, to spend time with Mr Matiazh in his village down the road, surrounded by fields and hills that frame the edge of this part of Ukraine and the entrance into Russia.
The slim man with a kind smile lives with his wife and two of their three sons, aged 16 and 11. Their eldest son, 29, who shares the same name as his father, is in the military as part of Ukraine’s territorial defence force.
‘I felt happiness and pain at the same time’
Andrii Matiazh junior took us to visit the humble, single-storey home. It was only a few days after he first was able to venture back to embrace his parents in the wake of Russia’s retreat.
They tried to describe that moment.
“My insides flipped upside down [with joy],” said his mother, Liubov, 46.
Her soldier son said: “I felt happiness and pain at the same time. You can’t understand these feelings. It is too hard to describe.”
‘I was shaking for 30 minutes’
The parents had a frontline seat for Russia’s full-scale invasion on 24 February given their village’s proximity to the border.
“I saw jets, helicopters, flying so low, they would fly between yards,” said the mother.
“I was shaking for 30 minutes. My youngest child was in hysterics.”
They said Russian soldiers took charge in the nearest town, Vovchansk, while the people made responsible for the villages came from parts of Ukraine’s Donetsk and Luhansk regions which have been under Russian control since Moscow’s first invasion back in 2014.
Residents of their village were offered Russian passports, the couple said.
“We didn’t accept, but the majority of civilians took passports,” said Liubov. “I believe they did that because of fear.”
The couple also alleged that Russian soldiers and their proxies would steal from properties in the area.
It added to a climate of mistrust and abuse, which gravely impacted the family just two days before Ukraine’s counter-offensive reached their area earlier this month.
‘I had bruising’
The father said he was told to attend a building behind the courthouse in the local town.
He said five individuals, working under the Russian occupation, were involved, including a distant relative.
“They took me to the second floor. I received three or four hits in my face,” he said.
“Then they tied up my hands behind my back, took off my shoes and socks, connected a metal cable to my small finger on my hands and to my foot. They laid me down and began to electrocute me.”
He said he was also blindfolded.
At one point, a different type of charge was used on his leg – he still has marks on one thigh.
“Capillaries in my eyes collapsed and my eyes became red. I had bruising. I even didn’t feel anything when they beat me in the face after the electricity,” Mr Matiazh senior said.
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‘I knew our soldiers were coming’
He said he was being interrogated about a local theft that he had nothing to do with.
It went on for two hours, before he was told he would be released but had to return within a couple of days with information – a threat the father took to mean that he needed to become an informant or face more torture.
Back home, he and his wife discussed trying to flee but they did not have enough money.
“I decided to hide somewhere in bushes, abandoned houses, and wait for our soldiers. I knew that our soldiers were coming,” he said.
He believes the counter-offensive that followed saved his life.
His eldest son said: “All the bad police guys ran away to Russia.”
Asked how he felt after hearing his father’s account of torture and conditions in the village during the occupation, Andrii junior said: “Creepy and terrible.”
He wondered whether his connection to the military might have been a reason why his father was targeted, noting that a number of his classmates had joined the police and knew he was a soldier. “I am not accusing anyone but someone… betrayed me,” he said.