(NewsNation) — Alexei Navalny is a Russian opposition leader, lawyer and anti-corruption activist. He has organized antigovernmental demonstrations and ran for office to advocate reforms against corruption in Russia and against President Vladimir Putin.

In 2020, the top opposition leader infamously survived a poisoning with a nerve agent that he blames on the Kremlin. Russian officials have denied his accusations.

A Russian court on Tuesday convicted Navalny of fraud and contempt of court, sentencing him to nine more years in prison. He is already serving 2½ years in a penal colony east of Moscow for a parole violation. 

Navalny is known for exposing corruption in the Kremlin and holding large protests with thousands of attendees.

After recovering from his poisoning in Germany, he was arrested upon returning to Russia in January 2021, triggering the biggest protests seen in the country in recent years. The next month, a Moscow court ordered him to prison for violating terms of his parole on a 2014 embezzlement conviction that the European Court of Human Rights deemed to be “arbitrary and manifestly unreasonable.”

Authorities continue to crack down on his organization, associates and supporters. Last month, Russian officials added him and a number of his colleagues to a state registry that labeled them extremists and terrorists.

Several criminal cases have been launched against Navalny individually, leading his associates to suggest the Kremlin intends to keep him behind bars indefinitely.