Ninth Chief Directorate (KGB)

The Ninth Chief Directorate (Russian: Девя́тое управле́ние, romanized: Devyatoye upranvlenie), colloquially known as the Devyatka (Девятка), was a security force of the KGB responsible for the protection of high-ranking Communist Party of the Soviet Union (CPSU) members and important government facilities such as nuclear weapons stocks. It consisted of 40,000 uniformed troops that provided bodyguard services to the CPSU leadership and their families, operated the Moscow VIP subway system, and the Vertushka secure government telephone system that linked high-level government and CPSU officers.

Source: Wikipedia — Ninth Chief Directorate (KGB) (CC BY-SA 4.0)