Russian journalist and opposition figure Vladimir Kara-Murza has been transferred to an unknown location, his wife, Evgenia Kara-Murza, reported on Jan. 29.
Kara-Murza was sentenced to 25 years in prison in April 2023 for condemning Russia's all-out war in Ukraine.
"We just learned that after four months of solitary confinement my husband "left" (as put by an official) the strict-regime penal colony in Omsk in an unknown direction," Evgenia Kara-Murza said on X.
A friend of Kara-Murza, Alexander Podrabinek, posted on Facebook that he sent him a letter via the prison postal service three days ago, but received a response that the letter could not be delivered to the penal colony in Omsk "since the addressee has left for another institution."
In a similar case, the family and team of Russian opposition politician Alexei Navalny lost contact with him for almost three weeks in December after he was transferred to a different penal colony.
The disappearance prompted concerns about the state of his health amid an intensifying crackdown on the opposition by Russian dictator Vladimir Putin in the run-up to the 2024 presidential election.
"The situation with Alexei is a clear example of how the system treats its political prisoners, attempting to isolate and suppress them," Ivan Zhdanov, head of the Anti-Corruption Foundation established by Navalny, said in reaction.
Kara-Murza was arrested in Russia on April 11, 2022, and charged with "treason," "spreading false information" about the Russian military, and belonging to an "undesirable" foreign organization.
Kara-Murza, who is also a British citizen, went on to liken his trial to that of the show trials in the 1930s during the Stalinist purges and that he only regretted the failure on his part of convincing people of the threat Russian President Vladimir Putin posed.
Kara-Murza was close to opposition politician Boris Nemtsov, who was shot dead by the Kremlin in 2015.
In 2015 and 2017, Kara-Murza said he had been poisoned by the Russian authorities in retaliation for his efforts to persuade Western nations to impose more economic sanctions on Russia.