Russia's Federal Security Service (FSB) on Wednesday detained members of Allya Ayat, a new-age religious group originating in Kazakhstan and banned as "extremist" under Russian law, in the city of Rostov-on-Don, state news agency TASS reported.
Russian authorities are on high alert following a mass shooting at a concert hall near Moscow last Friday in which at least 139 people were killed. Islamic State claimed responsibility for the attack.