The FSB security service and the police "identified and thwarted" the activities of cells belonging to an international internet community "created for the propaganda of terrorist ideology and recruiting of fighters for the Islamic State", the FSB said in a statement.
The cells were based in Russia's central Sverdlovsk, Tyumen and Chelyabinsk regions, where the FSB said it conducted 27 searches yesterday at the homes of alleged members, seizing computers and mobile phones containing jihadist propaganda material as well as pistols, hand grenades and explosives.
It also said the online community has more than 100,000 members spread throughout the former Soviet republics of Central Asia and the Middle East.
The FSB said in February it had detained seven alleged IS members in the Sverdlovsk region who were plotting to carry out terror attacks in major Russian cities, including Moscow and Saint Petersburg.
More From This Section
Both IS and Al-Qaeda's Syrian affiliate Al-Nusra Front have called for attacks in Russia in response to Moscow's bombing campaign in support of Syrian President Bashar al-Assad.
Moscow has said part of the reason why it launched a bombing campaign in Syria last year was to prevent IS jihadists and other extremists from perpetrating attacks in Russia.
According to FSB figures released in December, nearly 2,900 Russians are fighting or have fought with the jihadists in Iraq and Syria.