TY JOUR TI Theoretical and legal foundations of countering extremist activity in the Russian Federation KW national security KW extremist activity KW counteraction JO BULLETIN OF THE MOSCOW UNIVERSITY OF THE MINISTRY OF INTERNAL AFFAIRS OF RUSSIA AU Shenshin, V.M. AU Utkin, N.I. PY 2026 IS 0 PB Moscow University of the Ministry of Internal Affairs of Russia named after V.Ya. Kikot