The highest court in Chechnya sentenced Stanislav Klykh and Mykola Karpyuk to 20 and 22-and-a-half years in prison respectively.

They were found guilty of killing Russians while fighting alongside Chechen separatists in 1994 and 1995.

The North Caucasus region fought two wars with Moscow but is now ruled by a pro-Kremlin figure, Ramzan Kadyrov.

Their lawyer Ilya Novikov also represented Ukrainian pilot Nadiya Savchenko, who was freed on Wednesday in a prisoner swap with two alleged Russian soldiers who fought in eastern Ukraine.

Novikov hinted that the pair could also be freed.

“Karpyuk got 22-and-a-half years, Klykh got 20 years. Very much to the point, we saw yesterday that sometimes these words amount to less than zero,” Novikov wrote on his Facebook page.

Karpyuk and Klykh were arrested while making separate visits to Russia in 2014. Their supporters argue they had never been in Chechnya prior to the case.

Ukraine’s foreign ministry spokeswoman Mariana Betsa said the decision was a “shameful verdict in a fabricated case” and vowed to fight for their freedom.

Russia says the duo were fighting Russian soldiers as part of a squad from the Ukrainian nationalist organisation UNA-UNSO. They were accused of killing dozens of Russian soldiers.

Karpyuk is a well-known nationalist in Ukraine, an ally of Dmytro Yarosh, ex-leader of Right Sector nationalist group vilified by Moscow. Yarosh has accused Russian security services of luring Karpyuk into Russia to arrest him.

Klykh is a journalist who has lectured on history at a Kiev university.

The case reportedly rests on the testimony of a single Ukrainian who is already serving a long sentence in a Russian jail.

Russian rights group Memorial analysed the case and said there were “many signs that evidence in the case is based on slander and false confession.”

It added that even if the accusations were true, the men should have not been prosecuted due to Russia’s statute of limitations.

Reports said the Ukrainians complained at the trial that they had been tortured, beaten and not allowed to sleep but the jury was asked to leave the courtroom during these accounts.

Russia fought two messy wars in Chechnya against separatists calling for an independent state.

The military campaign ended with the installation of Akhmad Kadyrov, a former separatist warlord, at the helm of the war-torn region. His son Ramzan took power after his 2004 assassination.

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