Two British citizens and a Moroccan were sentenced to death Thursday for fighting on Ukraine’s side, in a punishment handed down by the country’s pro-Moscow rebels.

A court in the self-proclaimed Donetsk People’s Republic found the three men guilty of working toward a violent overthrow of power, an offense punishable by death in the unrecognized eastern republic. They were also convicted of mercenary activities and terrorism.

Russia’s state news agency RIA Novosti reported that the three – Aiden Aslin, Shaun Pinner and Saaudun Brahim – are set to face a firing squad. They have a month to appeal.

The separatists argued that the three fighters were “mercenaries” not entitled to the usual protections afforded prisoners of war. They are the first foreign fighters to be sentenced by Ukraine’s Russian-backed separatists.

Aslin’s and Pinner’s families had contended that the men, who are both said to have lived in Ukraine since 2018, were “long-serving” members of the Ukrainian military.

British Foreign Secretary Luz Truss condemned the sentencing as a “sham judgment with absolutely no legitimacy.” Prime Minister Boris Johnson’s spokesman Jamie Davies said that under the Geneva Conventions, POWs are entitled to immunity as combatants.

The three men fought alongside Ukrainian troops. Pinner and Aslin surrendered to pro-Russian forces in the southern port of Mariupol in mid-April, while Brahim did so in mid-March in the eastern city of Volnovakha.

The Russian military has argued that foreign mercenaries fighting on Ukraine’s side are not combatants and should expect a long prison term, at best, if captured. Another British fighter captured by the pro-Russian forces, Andrew Hill, is awaiting trial.

Meanwhile, Russian forces pounded the eastern city of Sievierodonetsk in fierce, street-by-street combat that Ukrainian President Volodymyr Zelenskyy said could determine the fate of the Donbas, the country’s industrial heartland of coal mines and factories.

Moscow-backed separatists have been fighting Ukrainian troops for years in the Donbas and held swaths of territory before the invasion.

“Fierce battles continue in the city itself, street battles are taking place with varied success in city blocks,” Serhiy Haidai, governor of Luhansk province. “The army of Ukraine is fighting for every street and house.”

Sievierodonetsk is part of the very last pocket of Luhansk that the Russians have yet to seize.

Zelenskyy called the painstaking fight for the city the “epicenter” of the battle for the larger Donbas, which is comprised of Luhansk and Donetsk provinces.

“In many ways, it is there that the fate of our Donbas is being decided,” Zelenskyy said Wednesday in his nightly video address, which was recorded in the street outside his office in Kyiv.

Ukraine’s top military official said the situation on the front line is “very difficult” and calls for “very quick” weapon supplies.

Defense Minister Oleksii Reznikov said in a Facebook post that up to 100 Ukrainian troops are being killed every day. “We as a country can’t afford to bleed, losing our best sons and daughters,” he said.

In other developments:

— Haidai said Russian forces are also targeting Lysychansk, the city that neighbors Sievierodonetsk, with “day and night shelling,” and trying to storm a key road leading from Lysychansk to the southwest.

— Russia claimed it struck a training facility west of the capital, far from the front lines. Russia’s Defense Ministry said it used air-launched missiles against a Ukrainian military base in the Zhytomyr region where it alleged mercenaries were being trained.

There was no immediate response from Ukrainian authorities to the Russian claims. Moscow has repeatedly accused Ukraine of using mercenaries in the fighting. (Text, excluding headline, courtesy of AP)

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