March of Dissent rallies demanding freedom of assembly took place in at least 10 constituent territories of the Russian Federation, a Russian Interior Ministry spokesman said on Saturday.
He said protest rallies were held in the cities of Vladivostok and Blagoveshchensk in the Russian Far East, Barnaul in the south Siberian Altai region, Stavropol in southern Russia, Petrozavodsk in the northwestern republic of Karelia and other places.
However, he said "all the events were rather sparsely attended" with a relatively small number of police deployed to ensure public order.
He also said there were "no serious disturbances of public order."
At least 135 opposition protesters who took part in unauthorized March of Dissent rallies in Moscow and St. Petersburg were detained.
An estimated 200 protesters turned out for the rally in downtown Moscow with 75 hauled away in police vehicles.
Some 300 reporters were on hand to cover the event.
The protest rally in Russia's second largest city, St. Petersburg, was attended by 100 people, 60 of whom were detained by police.
One police officer in Moscow was injured during a confrontation with the protesters and was reported to be "bleeding in the neck area."
The circumstances of his injury were unclear.
According to Moscow police department spokesman Viktor Biryukov, the officer was pushed by a female protester.
"As a result, he fell and cut his face on broken glass," Biryukov said.
Police grabbed Russian opposition leader Boris Nemtsov, a former deputy prime minister, and Sergei Udaltsov, leader of the Leftist Front opposition group.
Nemtsov told a RIA Novosti correspondent on the telephone that he was being held at Moscow's Tverskoi district police station.
"I am being charged under Article 19.3 of the Code of Administrative Violations - that is to say, disobeying police," he said.
The charge carries a fine of up to 1,000 rubles [$33] or a 15-day arrest.
He dismissed the charges and said he would not sign any papers.
Nemtsov and Udaltsov were later released.
Earlier in the day, several young people chanting "Shame!" tried to march down Triumfalnaya Square. Police ordered them to stop, then dragged them to buses and took them to a local police station.
Russia's opposition groups went ahead with the rally in defiance of a city government ban.
In mid-July, city officials authorized a bike festival on Triumfalnaya Square from July 30 through August 1 in what many saw as a deliberate move to foil the opposition's plans.
Moscow city authorities have regularly turned down requests from Russian opposition groups to stage March of Dissent rallies.
Nearly 200 opposition protesters were detained during a rally on May 31.
The crackdown caused public outrage as riot police outnumbered demonstrators and people with disabilities as well as a World War II veteran were reportedly among those detained.
MOSCOW, July 31 (RIA Novosti)
Opposition groups hold Marches of Dissent on the last day of each month with 31 days in defense of their right to freedom of assembly, as enshrined in Article 31 of the Russian Constitution.
