The head of a Russian Islamic State branch was reportedly killed early on Sunday as part of a raid, according to the Russian FSB security service. The leader of a North Caucasus ISIS branch was killed in a special operation conducted by Russian Federal Security Service forces in collaboration with the Ministry of Interior, the security service said in a statement Sunday. Rustam Magomedovich Aselderov, known as Abu Muhammad, and four militants close to him were killed in an exchange of fire with government forces Saturday near Makhachkala, the capital of Dagestan, the statement from the FSB said. He was wanted in connection with the 2013 terrorist attacks in the city of Volgograd, where suspected suicide bombers detonated explosives at a rail station and a trolley bus, killing more than 30 people. Aselderov has been known to Russian law enforcement as an active member of Dagestan terrorist cells since 2007. In 2012, he became in charge of Dagestan's unit of the internationally recognized terrorist organization "Imarat Kavkaz." In 2014, he was "one of the first" to pledge allegiance to Islamic State. In late June 2015, Aselderov was appointed the head of the so-called Vilayat Kavkaz, established on the Russian territory by so-called Islamic State, on the orders of its leader, Abu Bakr al-Baghdadi. Among his "duties" as an emir were the planning of terrorist acts in Russia's Northern Caucasus and in central Russia, the FSB said.