Captured British fighter Aiden Aslin is photographed with gashes and a swollen eye after being taken by Russian troops in a move said to be motivated by propaganda.
Amid fears of torture in Ukraine, his picture has been shared by a pro-Donetsk People's Republic Telegram account.
The 28-year-old, who has fought for the country's marines for four years, also had a large cut across his forehead.
Aiden, widely known by his social media name Cossack Gundi, is originally from Newark, Nottinghamshire and previously fought Isis in Syria.
It is not yet known where he is being held as he MP in the UK demands answers as fears grew that soldiers were being tortured.
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His battalion were forced to surrender earlier this week in the besieged city of Mariupol as Russian forced moved in.
It is possible injuries from a rifle butt on his forehead.
He was shown with his wrists in handcuffs in the photos released today.
Speaking from her home in Balderton, Notts., Aiden's mum Ang Wood said: "It's Aiden I can't deny it. It's him.
“They are his tattoos. There is a faint hope it is a doctored image but I can't see it.
"I now hold Vladimir Putin to the terms of the Geneva Convention.
“Aiden is a serving member of the Ukrainian armed forces and as such is a prisoner of
war and must be treated with humanity.
"It already looks like he has been beaten up.
"It is time now for the British Government to get involved. and help secure Aiden's release because he is still a British citizen.
"Possibly there is hope for a prisoner swap arranged by the Ukrainians.
"I'm in bits. My son will be scared just as we are."
It has been reported that it is likely he has been captured by Vladimir Putin's murderous regime for possible propaganda - but could ultimately be freed as part of a prisoner exchange.
In a conversation before he and his unit were captured, he said: "It's been 48 days.
"We tried our best to defend Mariupol but we have no choice but to surrender to Russian forces.
"We have no food and no ammunition. It's been a pleasure everyone, I hope this war ends soon."
He has dual citizenship and has been a member of the Ukrainian army for years.
His brave battalion ran out of supplies and ammunition following 48 days of battle.
He had posted videos of the fight against Russian forces since the start of the invasion of Ukraine.
But fears grew of his capture - and answers are now being demanded back in the UK.
Robert Jenrick, the MP for Aiden's hometown of Newark in Nottinghamshire, tweeted yesterday: "I am working with the foreign office to track the whereabouts and secure the release of my constituent.
"Aiden chose to risk his life because he believes passionately in the Ukrainian people’s right to live in freedom and democracy."
Aiden's social media account is being run by friends while he is on the frontline.
They tweeted a picture of the British national today and vowed to keep his plight 'in the public eye'.
"Just got this, it looks as if they have gotten ahold of Aiden," the tweet read.
"F***ing pukes have worked him over too by the looks of it. We're going to keep in the public eye every day until he's exchanged."
