Eduard Limonov, head of the Other Russia party, and the others were detained Friday on charges of "attempting to hold an unsanctioned rally," RIA Novosti said.
Police arrested a 14 people at a parallel rally in St. Petersburg.
Opposition parties hold rallies around Russia on the last day of months with 31 days to protest what they consider attempts by the Kremlin to limit their rights to freedom of assembly that are guaranteed by Article 31 of the Russian constitution.
In June, Russia passed a law increasing fines for unsanctioned rallies from $30 to $9,300.
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