Authorities dispersed banned opposition demonstrations - the Marches of Dissent - in Moscow and St. Petersburg this past weekend, detaining 250 and 170 people in the two cities, respectively.
Rights groups, oppositionists and journalists have accused Russian police of abusing their authority and violating the law during the dispersal.
Hans-Gert Pottering said the European Parliament will stay in close touch with the Russian opposition and will follow developments in Russia.
Human rights advocates in Russia and abroad have criticized the Kremlin for tightening its grip on democracy and human rights ever since Vladimir Putin took office in 2000. However, polls show that a majority of Russians support the country's leader for the stability and economic growth Russia has enjoyed during his tenure.
Some 9,000 policemen were deployed to provide security in Moscow during the Saturday march, which gathered supporters and members of the Other Russia organization that includes the People's Patriotic Union led by former Premier Mikhail Kasyanov, the banned National Bolshevik Party, the United Civil Front led by world chess champion Garry Kasparov and the Republican Party.
Kasparov was detained and held by police until late evening. He accused riot police of "a bandit attack on Russian citizens."
But Russian authorities have denied that any laws were broken during the March of Dissent in Moscow, saying riot police acted in a tough but totally legal manner.