- 1974 - 1982 maj. gen. Vladimír Stárek
- 1982 - 1988 col. Zdeněk Wiederlechner
- 1974 - 1977 col. Jaroslav Saksl
- 1975 – 1979 lt.col. Karel Vrba
- 1976 - 1981 col. Viktor Hladný
- 1977 - 1986 lt. col. Jiří Dvořák
- 1979 - 1981 lt. col. Oldřich Mézl
- 1983 - 1988 lt. col. Josef Sámek
- 1983 - 1985 lt. col. Antonín Král
- 1986 - 1988 deputy chief lt. col. Karel Vykypěl
By order No. 15/1974 from 20 May 1974, federal minister of interior Jaromír Obzina dissolved the existing Main directorate of the counterintelligence on 30 June 1974 and established the Directorate of the counterintelligence for the fight against the external enemy (Directorate II of the Federal ministry of interior), the Directorate of the counterintelligence for the fight against the internal enemy (Directorate X of the Federal ministry of interior), and the Directorate of the counterintelligence for the protection of the economy (Directorate XI of the Federal ministry of interior). The newly established Directorate X was to direct and organise couterintelligence activities on the entire territory of Czechoslovakia against the domestic opposition and non-conformist groups of citizens. It was to concentrate mainly on “organisers of enemy groupings and main bearers and disseminators of right-wing opportunism, revisionism, Zionism, Trockyism, Maoism, Ukrainian nationalism and bourgeois ideologies in the field of societal suprastructures – particularly in culture and art, science, at universities, in the mass media ...” and to uncover “persons acting toward disturbing the state church policy in the ČSSR.”
Directorate X of the Federal ministry of interior was subordinated to the 1st deputy minister of interior of the ČSSR maj. gen. Ján Hanuliak. In 1979-1985 Directorate X was in the competence of 1st deputy minister of interior maj. gen. Ján Kováč, in 1985-1988 deputy minister of interior maj. gen. Alojz Lorenc.
The internal structure of Directorate X:
- Organisational and operational section (internal section until 1986)
- Analytical, information and planning section (analytical, information, planning and monitoring section until 1986)
- Personnel group (Personnel and schooling department until 1986)
- Chief’s inspection (Inspection of the Directorate chief until 1986)
- Defence group (Defence preparation and protection until 1986)
- Section 1 of Directorate X – right-wing and opportunistic forces:
- Department 1 – leading persons of the right-wing and Czechoslovak emigration from among leading persons of the right-wing
- Department 2 - leading persons from among former staff members of the state apparatus
- Department 3 – operative completion of selected action.
- Section 2 of Directorate X – culture, science, mass media and centres of ideological diversion:
- Deaprtment 1 – ministry of culture and art associations, foreign ideo-diversion centres and publishers,
- Department 2 – science, health care, enemy ideo-diversion centres on the line of science and protection of societal organisations of exceptional importance,
- Department 3 – Czechoslovak radio, television, film, Czech press agency ČTK, International journalist organisation, Czech and Cechoslovak union of journalists and respective ideo-diversion centres abroad.
- Section 3 of Directorate X – youth, schools, foreign students and sport:
- Department 1 – ministry of education, universities, Institute for foreign school contacts, International student union and Czechoslovak students abroad,
- Department 2 – counterintelligence protection of youth and sport organisations and institutions, extreme trends among youth.
- Section 4 of Directorate X – anti-socialist forces:
- Department 1 – Zionism, jewish nationalism, pro-Zionist intelligentsia in science, pro-Zionist youth and world Zionist centres,
- Department 2 – Organisation of Ukrainian nationalists (OUN), Narodno-trudovoy soyuz (NTS), centres of so-called Eastern emigration, Anti-bolshevik bloc of countries (ABN), Radio Liberty,
- Department 3 – former representatives of reactionary political parties, counter-revolutionary and extreme forbidden organisations, former punished agents of enemy foreign intelligence, protection of the parties of the National front, Greek emigration, Trockyism and Maoism,
- Department 4 – illegal press materials and anonymous threat letters, terror, illegal arms, monitoring of records and processing of enemy persons.
- Section 5 of Directorate X – enemy elements in churches and sects and foreign church centres:
- Department 1 – Roman-Catholic church and its foreign centres,
- Department 2 – non-Catholic churches and their foreign centres.
Directorate X operated until 1988 when minister of interior Vratislav Vajnar, upon a motion by the Communist party of Czechoslovakia, issued order No. 12/1988 on 22 July 1988 on the establishment of units of the Federal ministry of interior and units subordinated to the Federal ministry of interior. A major re-organisation of the State security took place which re-joined both units responsible for the fight against the “external” (Directorate II) and against the “internal” (Directorate X) enemy with the unit for the protection of the economy (Directorate XI). As of 1 August 1988, a consolidated Main Directorate of the counterintelligence of the National security corps was created (code name Directorate II of the National security corps) which was subordinated to the 1st deputy minister of interior.