MOSCOW — The police arrested more than 200 people in a roundup on Sunday that the local news media linked to an obscure right-wing movement that had been calling for a repeat of the Russian Revolution, timed near its 100th anniversary.

The movement, called Artpodgotovka, or Art Preparation, had agitated in online posts for followers to prepare for revolution, but had not been widely known or taken seriously before this weekend.

The tiny turnout did not seem to pose any real threat. The people who followed directions in the group’s online posts and showed up at noon on Sunday on Manezh Square, in the center of Moscow, milled about in seeming confusion before officers arrested them.

“It was a very strange picture,” said Aleksandr Verkhovsky, the director of Sova Center, a nongovernmental organization that monitors right-wing groups in Russia.