Russian opposition leader Alexei Navalny has been detained at a Moscow airport after returning from Germany yesterday, the prison service has said.
The service said he was detained for multiple violations of parole and terms of a suspended prison sentence and would be held in custody until a court made a decision in his case.
Mr Navalny, who is President Vladimir Putin's most prominent and determined foe, has spent the last five months in Germany recovering from a nerve agent attack that he blames on the Kremlin.
He decided to leave Berlin of his own free will and was not under any pressure to leave from Germany. The prison service made the announcement after the flight carrying Mr Navalny landed in the Russian capital, though at a different airport to the one scheduled. It was a possible attempt to outwit journalists and supporters who wanted to witness his return.