Russian political activist Sergei Udaltsov was released from prison on Tuesday after serving a sentence of four and a half years for organising anti-Kremlin protests, his wife said.
Udaltsov and co-defendant Leonid Razvozzhayev were convicted in July 2014 of fomenting mass riots across Russia ahead of Vladimir Putin's inauguration to a third term as president in 2012.
Human rights organisations have said their prosecution was politically-motivated and the punishment too harsh.
"Sergei Udaltsov was freed today after spending 4.5 years behind bars," his wife Anastasiya Udaltsova wrote on her Facebook page.
Udaltsov, 40, was the leader of a banned radical leftist group who rose to prominence during the protest movement against Putin's return to the Kremlin.
Charges against him and Razvozzhayev were based on a film broadcast on a Russian TV channel which alleged that he planned an uprising funded by a Georgian lawmaker.
His release was welcomed by Russia's leading opposition politician Alexei Navalny. "Congratulations to Sergei Udaltsov on being freed! He spent 4.5 years in prison due to a fabricated political case," he tweeted.
Udaltsov spent his term in a penal colony in central Russia's Tambov province, going on hunger strike several times in protest.
Razvozzhayev was released in April.