MOSCOW (Reuters) - Russian law enforcement officers detained 140 people at a Muslim prayer room in Moscow on Friday as part of a search for Islamist militants, Russian news agencies quoted Federal Security Service (FSB) officials as saying.
FSB and Federal Migration Service officers took the detainees, including more than 30 foreigners, to police stations near the site in southern Moscow, state-run RIA cited the FSB's Moscow branch as saying.
There was no indication of any link to the April 15 attack at the Boston Marathon, in which U.S. authorities believe two ethnic Chechen brothers with roots in Russia's North Caucasus set off bombs that killed three people and wounded 264.
President Vladimir Putin said in a television appearance on Thursday that the Boston bombings justified his tough line against militants in the North Caucasus and that Russia and the United States must step up cooperation against militants.
RIA reported that law enforcement authorities said some people who had been at the prayer room in the past had joined an Islamist insurgency in the North Caucasus.
But government critics say such raids are aimed largely at flushing out illegal migrants from the ex-Soviet republics of the South Caucasus and Central Asia, and to show that the authorities are taking action against Islamists.
RIA said the detainees were taken to police stations for identification and questioning, and there was no immediate word on whether any would be charged. State television showed men lining up and boarding a police bus after being detained.
About 300 people were detained in a similar sweep in St. Petersburg in February, and most were swiftly released.
The RIA report named one native of Chechnya it said had joined the insurgency after visiting the prayer room, and said he had been killed in October 2011. FSB and migration service officials declined immediate comment.
(Writing by Steve Gutterman; Editing by Michael Roddy)