Moscow police said in a statement the "activity" of the Islamic Revival Party "has been intercepted," RIA Novosti reported Monday.
Hand grenades, weapons, ammunition and extremist literature were found in searches of the suspects' homes, police said.
The Islamic Revival Party is a registered political party and is the main political opposition group in Tajikistan, a former Soviet Union republic, where it has called for creation of an Islamic republic.
The party has a following among migrants to Russia.
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