"I was told that there were four minors in one of the police vans, but I have no information on where they are being taken to. When I figure out where they are, I'll start looking into it. They were detained at Pushkinskaya [square in central Moscow]", Bunimovich said.
Earlier in the day, the Russian Interior Ministry's Main Directorate for Moscow said that some 1,500 people attended an unauthorised event in central Moscow and some 600 were arrested over violating public order.
Police reportedly used megaphones to urge protesters at the Pushkinskaya, one of Moscow's busiest squares, to refrain from violating public order and blocking passage for other people. Some of the protesters were wearing black masks, the reporter added.
The event was initiated by the Libertarian party over some candidates being excluded from the Moscow city council elections. The organizers rejected to hold the rally at the location proposed by the city authorities and instead called on people to walk through the circle of boulevards and squares around Moscow's historical center.