Russian police and security agents have detained 140 people following prayers at a mosque in Moscow.
A statement from the Federal Security Agency reported by Russian news agencies said that those detained at the Dorul Arqom Islamic cultural center on April 26 included 30 citizens of unspecified foreign countries.
RFE/RL’s Tajik Service reports that most of those arrested were ethnic Tajiks who were taken to various police stations.
At one station, 25 people were held, with eight later released.
Those who remained in detention at the station told our correspondent that they were being held without charges.
The detentions come a week after the two suspects in the fatal Boston Marathon bombings were identified as originating from Russia's North Caucasus republic of Chechnya and sympathizing with Islamic extremists.
With reporting by AP