Eight alleged leaders of the Islamic sect Hizb ut-Tahrir have been detained in Russia's Republic of Tatarstan.
Russia's Federal Security Service said on October 14 that the detained individuals are facing charges of terrorism.
Police found a "significant amount" of printed materials and electronic texts with "extremist content" at 20 addresses linked to the suspects.
If found guilty, the suspects face up to 10 years in jail.
Some of the suspects have been sentenced for taking part in Hizb ut-Tahrir's activities in the past.
Hizb ut-Tahrir is a London-based Sunni political organization that seeks to unite all Muslim countries into an Islamic caliphate.
Russia's Supreme Court banned the group in 2003, branding its members and supporters as "extremists."