Russian police arrested about 20 protesters on Wednesday night at a central Moscow square where demonstrators had moved after police uprooted them from a camp, the latest move in a broadening crackdown on the forces opposing President Vladimir Putin.

The detentions at Kudrinskaya Square come as the opposition tries to maintain momentum following a series of massive protests over the winter.

Several hundred demonstrators had gathered at the square outside one of the city's iconic Stalinist Gothic skyscrapers after an early morning police raid on activists who had set up a camp in a park in the center of Chistoprudny Boulevard.

Video from the square streamed by Ekho Moskvy radio's website Wednesday night showed police forcing demonstrators into buses while other protesters yelled angrily. Hundreds of demonstrators remained on the square after the arrests

Police said about 20 people were detained.