Opposition groups in Russia have vowed to continue holding unsanctioned demonstrations to protest the results of the December 4 parliamentary elections despite the detention of some 560 protesters in Moscow and another 250 in St. Petersburg less than 24 hours ago.
Opposition groups have been using social-networking sites to organize rallies.
One group calling itself "Against the Party of Swindlers and Thieves" -- a reference to the United Russia party of President Dmitri Medvedev and Prime Minister Vladimir Putin -- is calling for protests to start every day at 7:00 p.m. local time.
A Facebook page called "Demonstrations For Honest Elections
" is urging Muscovites to attend a protest on Moscow's Revolution Square and asking Russians across the country to protest as well. It had more than 11,000 "likes" by midday on December 7.
The Federation of Russian Automobile Owners has vowed to cause traffic jams in Moscow on December 10.
Courts were also due to begin hearing the cases of some of those detained in the December 6 protests.
Many of those arrested the previous day and sentenced on December 6 received 15-day sentences for their actions.
Official election results showed United Russia receiving a far smaller percentage of the vote than in the last election but still enough to win more than half the seats in parliament.
Opposition groups say the vote was rigged.
Former Soviet leader Mikhail Gorbachev says he believes the Russian authorities should annul the vote results and hold a new election.
Gorbachev told the Interfax news agency that the authorities must hold a fresh election or deal with a rising tide of discontent.
"More and more people are starting to believe that the election results are not fair," he told Interfax. "I believe that ignoring public opinion discredits the authorities and destabilizes the situation."
The authorities, Gorbachev said, "must admit that there have been numerous falsifications and ballot stuffing."
compiled from RFE/RL Russian Service and agency reports