Matovnikov took part in the First and Second Chechen Wars, in several special operations, including in the North Caucasus. He was one of the leaders of the storming of the hospital in Budyonnovsk, participated in the anti-terrorist operation in the "Nord-Ost" on Dubrovka, and investigated the circumstances of the storming of the school in Beslan. In Chechen circles he had the nickname "Chekist".