Two British men captured by Russian forces and accused of being mercenaries have appeared in court on charges that carry a possible death penalty.
Aiden Aslin, from Newark in Nottinghamshire, was seen in a Telegram video alongside Shaun Pinner, from Bedfordshire, and Saaudun Brahim from Morocco.
They are being held in the self-proclaimed Donetsk People's Republic, a breakaway region in Ukraine's east.
The men say they were serving with regular military units in Mariupol, so should be protected as prisoners of war by the Geneva Convention.
A third Briton, Andrew Hill, also faces charges after being captured in the Mykolaiv area. His affiliation is unclear.
The president of the Donetsk People's Republic, Denis Pushilin, has accused the men of "monstrous" crimes, such as trying to seize power and crimes against groups of people.
He said their trial would open at the region's supreme court.
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Mr Aslin's family said in a statement on Tuesday that it was a "very sensitive and emotional time" and that they were working with the Ukrainian government and UK Foreign Office to try to free the 28-year-old.
"Aiden is a much-loved man and very much missed, and we hope that he will be released very soon," they said.
The former care home worker joined Ukraine's armed forces as a marine in 2018 and has applied for citizenship, and has a Ukrainian fiancee.
Mr Pinner was filmed in April saying that he had been captured while defending Mariupol, his adopted city.
His family stressed at the time that he was "not a volunteer nor a mercenary, but officially serving with the Ukrainian army".
The 48-year-old told Sky News a few months before that he was on his fourth tour of duty in Ukraine after serving in the British Army for nine years.
He has lived in the country since 2018 and has a Ukrainian wife.
Deputy Prime Minister Dominic Raab said on Monday that the British government expected "the laws of armed conflict to be represented" and the Foreign Office would make "all the representations".
Russia's current focus in the war is to capture the eastern Donbas region, made up of Luhansk and Donetsk.
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