MOSCOW — A Moscow court has ordered Russian opposition leader Alexei Navalny to prison on charges that he violated the terms of his probation while he was recuperating in Germany from nerve-agent poisoning.

Navalny, who is the most prominent critic of President Vladimir Putin, had earlier denounced the proceedings as a vain attempt by the Kremlin to scare millions of Russians into submission.

The prison sentence stems from a 2014 embezzlement conviction that he has rejected as fabricated.

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The 44-year-old Navalny was arrested Jan. 17 upon returning from his five-month convalescence in Germany from the attack, which he has blamed on the Kremlin. Navalny has since released a phone call with a Russian agent in which the agent allegedly admitted to the poisoning.

Russian authorities deny any involvement.

Navalny's arrest has sparked massive protests across Russia, some of which have taken place in frigid temperatures. Thousands of Navalny's supporters have been arrested by Russian law enforcement in the weeks since he was taken into custody.