Russian authorities are concerned about the prospect of Islamist militants becoming more of a threat outside the heavily Muslim North Caucasus, which is plagued by an insurgency rooted in two post-Soviet separatist wars in Chechnya province.
The Interior Ministry said the detainees were members of the Islamic Revival Party, which was designated as an international terrorist group by Russia’s Supreme Court and banned.
Police searching places where the detainees were staying found nine hand grenades and other weapons and ammunition, as well as extremist literature.
It a statement the ministry said leaders and members of the group had been “conducting active recruiting at mosques in Moscow and also distributing extremist literature and drawing other people into illegal activity.”
It was not immediately clear whether the group banned in Russia was related to a legal opposition group in the mostly Muslim former Soviet republic of Tajikistan that has the same name. A ministry spokesman declined immediate comment.
President Vladimir Putin has repeatedly warned of the dangers of religious violence since his inauguration to a six-year term in May. His 13-year rule has been marked by the bloodshed in the North Caucasus and attacks outside the region by militants based there.
Attacks on government-backed Muslim leaders in the Volga River province of Tatarstan in July added to fears of a spread of Islamist violence.
Rights activists say the violence is fuelled in part of heavy-handed police tactics and intolerance for religious beliefs outside the mainstream.