The family of a British national have expressed concerns after he was captured by Russia while fighting in Ukraine.
Speaking to UK media, the family of 28-year-old Aiden Aslin have called for him to be treated "humanely" and released.
Footage broadcast on Russian state television showed a young man handcuffed and with a cut on his forehead.
Aslin's mother Ang Wood has said that her son has the same distinctive tattoos as the man seen in the video.
"Aiden is an active member of the Ukrainian armed forces and thus a prisoner of war," she told the Daily Telegraph.
"It already looks like he has been beaten. It's time for the British government to get involved to secure Aiden's release," she added.
The UK government says it is aware that a British national is being held and remains in contact with his family, amid hopes of a potential prisoner exchange.
The situation in Ukraine severely limits the ability of British services to obtain information and provide consular assistance, a government source added.
Aslin’s local conservative MP, Robert Jenrick, said he was working with the UK Foreign Office to “track the whereabouts and help 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," Jenrick wrote on Twitter.
Details about the capture of soldiers by either Russia or Ukraine during the war are difficult to verify.
'We tried our best to defend Mariupol'
Aiden Aslin -- also known as Johnny -- is originally from Britain but moved to Ukraine in 2018 and now holds dual citizenship, according to UK media.
A Twitter account attributed to Aslin has been regularly posting on social media since the start of the Ukraine war.
On Tuesday, the account said that the 28-year-old had been fighting alongside Ukrainian forces in the besieged city of Mariupol, but that he might soon "surrender".
"It's been 48 days, we tried our best to defend Mariupol but we have no choice but to surrender to Russian forces," the tweet read.
"We have no food and no ammunition. It's been a pleasure everyone, I hope this war ends soon."
In a separate Facebook post on Monday, the Ukrainian military brigade that has been defending Mariupol also said they were “running out of ammunition” and expected to be killed or taken prisoner soon.
Three days later, videos of Aslin appeared on Russian state television after his reported capture.
In a separate video, the same young man also appears to blame Kyiv for the war, allegedly labelling Ukraine's military as "criminals" who show a “lack of care for civilians”. It is unclear under what conditions the video was filmed.
Since the start of the war, Russia has used Ukrainian refugees as propaganda to portray Ukraine as the "aggressor".
An investigation by MediaZona soon exposed that one of these videos was manufactured by Russian intelligence and targeted at a Russian audience.
Aiden Aslin's family have told the Press Association that the alleged video confession is "propaganda".
The Twitter account attributed to the 28-year-old has previously posted messages of solidarity with Kyiv and Ukraine's armed forces, in contrast to the footage on Russian state television.