Yashin, a Moscow municipal deputy, held a "meeting with voters" on Sunday after a court struck down his permit request for a "Day of Free Elections." The event was organized to educate voters about their rights and coincided with the sixth anniversary of one of the largest anti-government protests in Russian history on Dec. 24, 2011.

Police in Moscow have detained opposition politician Ilya Yashin less than a week after he held an unsanctioned rally in the Russian capital.

"Police detained me outside my home. They are transporting me to the Krasnoselsky station accompanied by five officers," Yashin wrote on Twitter on Thursday.

Reports say that police seized Yashin's phone, keys and documents and that he would remain in custody until an unspecified court date.

Police visited the opposition politician at his home before Sunday's event, but eventually allowed 300 people to gather to hear him speak, Yashin said at the time.

Fellow opposition politician Dmitry Gudkov, whose movement triumphed in the municipal elections in Moscow three months ago, called Yashin's detention "pure revenge that goes beyond the law” in a Facebook post.

"Rays of support to Ilya."