Riot gear-clad Russian police violently crackdown on peaceful protests over Navalny's prison sentence

• Muscovites swarmed their city's streets in protest after Alexei Navalny was sentenced to 3.5 years in prison.
• Police responded with violence, arresting hundreds of demonstrators.
• The US is calling for the release of Navalny, who was poisoned in August and nearly died.

Dmonstrators and riot police filled Moscow's streets on Tuesday night after Alexei Navalny was sentenced to three and a half years in prison for violating the terms of a 2014 conviction that the anti-corruption campaigner has decried as politically motivated.

Muscovites were seemingly infuriated by the verdict, and not deterred from protesting by the show of force from police. There were also protests in other major Russian cities, including St. Petersburg, following the verdict.

Video clips showed law enforcement responding aggressively and violently to peaceful protesters, beating them even as they shouted that they were unarmed. A journalist was reportedly among those attacked by police, as hundreds were arrested.

The demonstrators demanded the release of Navalny and other political prisoners.

Navalny is Putin's most famous critic, and he's heading to prison

Navalny, Russia's most prominent opposition leader, was poisoned in Siberia in August with the nerve agent Novichok and nearly died. He accused Russian President Vladimir Putin of orchestrating the poisoning. Novichok has been used in the poisoning of other Russian dissidents. World leaders demanded answers from Russia, as Putin denied any involvement and at one point reportedly suggested Navalny poisoned himself.

The top Kremlin critic went to Germany for treatment, remaining there for several months, and was arrested in mid-January upon returning to Moscow. Navalny was accused of repeatedly violating the terms of his 2014 parole by not reporting to authorities in person - including while he was receiving treatment abroad after his poisoning. His detention sparked mass protests across Russia and crackdowns by authorities. Thousands of Russians have been arrested amid the demonstrations in recent days.

Navalny excoriated Putin during an impassioned speech in a Moscow court on Tuesday, while demanding his release. "This is happening to intimidate large numbers of people. They're imprisoning one person to frighten millions," he said of the case against him.

The US is calling for Navalny's immediate release

The State Department condemned Navalny's sentencing and noted that Europe's top human rights court concluded that his 2014 conviction was "unlawful and arbitrary" and "politically motivated."

"We reiterate our call for the Russian government to immediately and unconditionally release Mr. Navalny, as well as the hundreds of other Russian citizens wrongfully detained in recent weeks for exercising their rights, including the rights to freedom of expression and of peaceful assembly," Secretary of State Antony Blinken said in a statement.

There are growing calls, including from congressional lawmakers, for the US to issue fresh sanctions over Navalny's detention and sentencing. White House press secretary Jen Psaki on Tuesday told reporters that the Biden administration is reviewing a series of actions by Russia, including the treatment of Navalny, and once that assessment is completed it will determine what steps to take in response.