AP Photo/Anton Belitski Police officers detain Russian opposition activist and anti-corruption crusader Alexei Navalny, 38, center, on his way to attend a rally in Manezhnaya Square in Moscow, Russia, Tuesday, Dec. 30, 2014.

Alexei Navalny, an activist who led mass protests against Russian government corruption three years ago, has battled a series of fraud charges that critics say are meant to silence him, and he has spent the past ten months under house arrest.

On Tuesday evening, he broke house arrest to lead major new projects against Vladimir Putin’s regime.

Navalny was given a suspended sentence on Tuesday morning in an embezzlement case, while his brother Oleg was sentenced to three and half years in prison in the same case. Government critics have claimed that Navelny was kept out of prison for fear of setting off large protests, with his brother punished in his place.

But Putin’s biggest critic isn’t staying quiet. Upon leaving the court house, he called for Russians to take to the streets to protest the decision.

“The authorities are torturing and destroying relatives of their political opponents. This regime doesn’t deserve to exist, it must be destroyed,” he told reporters as he was escorted in a car for prisoners.

Not long after, Navalny broke his house arrest to join the opposition rally. Navalny posted a photo of himself on the Moscow metro on Twitter to show that he was joining the protest. The tweet reads, “Yes, there is this house arrest. But today I want to be with you. So I’m coming.”

Домашний арест-это да, но сегодня мне очень хочется быть с вами. Поэтому я тоже еду. #Манежка pic.twitter.com/xkWGX0Hp4F

— Alexey Navalny (@navalny) December 30, 2014

Less than forty minutes later, Navalny was arrested by Moscow police, as he and other protesters marched to Manezhnaya Square.

Навального задержали у Ритц Карлтон pic.twitter.com/7n1x0zWDQo

— Anton Belitskiy (@antonb_ru) December 30, 2014

Approximately 18,000 people registered for the rally on Facebook. It is not yet known how many are actually in attendance, but the crowd shown in photos around Twitter looks sizable.

AT LEAST 10-15K PEOPLE HERE. CANNOT SEE END OF THE CROWD #moscow #navalny pic.twitter.com/oPUSZ6pBs1

— Ilya Mouzykantskii (@ilyamuz) December 30, 2014

Малая Садовая прямо сейчас pic.twitter.com/LlRJcjMj7s via @paperpaper_ru

— Партия Прогресса СПб (@navalny7) December 30, 2014

As of 7:45pm Moscow time, approximately 22 protesters had been arrested by Russian police, according to OVD.info, a Moscow-based independent human rights monitor.

AP Photo/Ivan Sekretarev Police push supporters of Russian opposition activist and anti-corruption crusader Alexei Navalny away during unsanctioned protest in Manezhnaya Square in Moscow, Russia, Tuesday, Dec. 30, 2014.

AP Photo/Denis Tyrin Police officers detain a protester during unsanctioned protest in Moscow, Russia, Tuesday, Dec. 30, 2014.

Navalny was later brought to his home, where soldiers were stationed outside his front door, according to a recent tweet by Navalny. The tweet reads, “At first, they took [me] to the police station, but half-way through received new instructions. took [me] home, not letting [me] out of [my] apartment. Outside of the door are 5 soldiers of the 2nd police special units.”

Сначала везли в овд, на полдороги поступили новые указания. Привезли домой, из квартиры не выпускают. Под дверью пять бойцов 2-го оперполка

— Alexey Navalny (@navalny) December 30, 2014

The trouble for Navalny began in December 2012 when the Russian federal Investigative Committee accused Navally and his brother Oleg of defrauding the French cosmetics company Yves Rocher, by overcharging them $US800,000 for shipping services from a company run by the brothers. Yves Rocher Vostok, the Russian subsidiary that dealt with the Navalny brothers, never reported any problems with the company during their business relationship and only submitted a legal complaint at the urging of the government, according to the New York Times. The complaint was later withdrawn.

Many outside observers consider the case politically motivated. Germany’s commissioner for human rights, Christoph Straesser told Reuters that the case was “a further blow to critical civil society in Russia.” Others, like Sergei Aleksashenko, an economist-turned opposition figure, were more harsh.

“The authorities could have easily put Navalny in jail. But they understand that it would have led to a large wave of protests. So they will torture him through other means,” said Aleksashenko, referring to the imprisonment of his brother Oleg.”

A similarly thin fraud case was levied against Navalny in July 2013, leading to his house arrest in February.

You can see a livestream of the protests here:

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