THE mother of a Warrington aid volunteer who has reportedly died while being detained by Russian-backed separatists in Ukraine has expressed her anger.

Paul Urey, from Culcheth is reported to have died in captivity on Sunday after being captured by the Russian military along with fellow British national Dylan Healy, 22, on April 25.

The men were stopped at a checkpoint near the city of Zaporizhzhya in the south of the war-torn country and were accused of being ‘mercenaries’.

News surfaced this morning, Friday, that the 45-year-old had sadly died in custody, much to the anger of his mother, Linda.

Writing on social media, she said: “I'm truly angry.”

She said she had begged for the separatists to give her son back and branded them ‘murderers’, asking: “Why did you let him die?”

In a post, she said her son had been taken from her at birth, and after finding her, he had been taken from her again.

“Cruel, cruel world,” she added.

Speaking at the time of his capture, Ms Urey told Sky News she had begged her son not to go to Ukraine.

She added: “He said, 'Muma, I can't live with myself knowing people... need help to get to a safe place, I have to go. I would feel bad'.”

Warrington Guardian: Foreign Secretary Liz Truss says Russia must bear the full responsibility (Image: PA)Foreign Secretary Liz Truss says Russia must bear the full responsibility (Image: PA)

Daria Morozova, the human rights ombudsperson for the Moscow-backed separatist leadership in Donetsk, said Mr Urey, who was branded a British ‘mercenary’, died in captivity on Sunday of chronic illnesses and stress.

"From our side, he was given the necessary medical assistance despite the grave crimes he committed," she added.

A No, 10 Downing Street spokesman said the Foreign Office is ‘urgently investigating’ the ‘clearly alarming reports’.

Foreign Secretary Liz Truss said she was ‘shocked’ by reports of Mr Urey's death.

“Russia must bear the full responsibility for this,” she said in a statement.

“Paul Urey was captured while undertaking humanitarian work. He was in Ukraine to try and help the Ukrainian people in the face of the unprovoked Russian invasion.

“The Russian government and its proxies are continuing to commit atrocities. Those responsible will be held to accountable. My thoughts are with Mr Urey's family and friends at this horrendous time.”

Meanwhile, the Russian ambassador to Britain, Andrei Kelin, has been summoned to the Foreign Office over the reported death.

Ms Truss summoned the ambassador for a dressing down by a senior official amid concerns Mr Urey died while being detained by Russian-backed separatists.

Sir Tim Barrow, the second permanent secretary at the Foreign Office, was to urge Mr Kelin to clarify the status of Mr Urey and demand that Russia meets its obligations under international humanitarian law.