Spetsnaz

The (Russian: Спецназ - Подразделение Специального Назначения (Podrazdeleniye Spetsyalnogo Naznacheniya, literally: Special Purpose Forces or Russian Special Operations Forces) is the name of multiple factions in Call of Duty (series). You may be looking for: 
*Spetsnaz/Modern Warfare - The faction version seen in the original Modern Warfare (series) games.
*Spetsnaz/Black Ops - The faction version seen in the Black Ops (series) games.
*Spetsnaz/Modern Warfare (Reboot) - The faction version seen in the rebooted Modern Warfare (series) games.