According to Fontanka: “the submariners who died as a result of the state of emergency in the Northern Fleet are on the lists of personnel of the unit that is located in St. Petersburg. It is subordinated to the General Directorate of Deep-Sea Research of the Ministry of Defense, information about it is accompanied by the “Top Secret” stamp. This circumstance does not interfere with the fact that the global network is replete with details about the activities of the division, whose main focus is called intelligence.”
https://www.fontanka.ru/2019/07/02/152/