Security forces in Moscow have detained at least 600 protesters for participating in unsanctioned demonstrations over city council elections.
The zero tolerance crackdown came during the fourth week running of protests over the exclusion of a number of opposition candidates from city council elections in the Russian capital in September.
Numbers from the Russian arrest-monitoring group OVD-Info, cited by the Associated Press, put the number of people detained at 685. Russia's Interior Ministry has published a lower figure of 600 arrested.
The number taken into police custody during the protests appears, at present, to be lower than the number detained in a similar demonstration last week. Russian authorities said in the wake of widespread protests one week ago that 1,400 individuals had been detained.
The weeks of protests, which have rocked Moscow since mid-July, have been viewed as a symptom of discontent with the Kremlin-aligned United Russia Party. The Interior Ministry put the total number of protesters in Moscow on Saturday at about 1,500. Solidarity protests were also held in St Petersburg.
In the Russian capital, police lined out along the route responded with force against the demonstrators. Dressed in riot gear and balaclavas the security forces grabbed protesters from the crowd in Pushkin Square. The marchers had aimed at making their way along Boulevard Ring on the edge of Moscow despite police warnings that they would take active measures.
One of the excluded candidates, Lyubov Sobol, whose high-profile hunger strike has galvanised the demonstrators, was arrested by a dozen police in central Moscow and forced into a wagon. She could be heard demanding to be told why she was being held as she was seized.
The Moscow Times reported the protest leader was driven around for several hours without her phone before being taken to a police station. "Hello to all the brave Muscovites who came out today! Proud of you!" she later wrote on Twitter from the police station.
Ms Sobol, along with opposition candidates Ivan Zhdanov, Ilya Yashin, and Dmitry Gudkov are allies of opposition leader Alxei Nabalny, a prominent critic of Russian President Vladimir Putin. They have been barred from standing in the 8 September ballot over what elections officials have said were inconsistencies in signatures supporting their candidatures.
The barred Moscow politicians have said their disqualification is thinly veiled attempt to stop them running against Kremlin-backed incumbents.