TheState Security Service(SSS), also known as theDepartment of State Services(DSS), is the primary domestic intelligence agency of Nigeria. It is primarily responsible for intelligence gathering within the country and for the protection of senior government officials, particularly the Presidentand state governors.
It is one of three successor organisations to the National Security Organization(NSO), dissolved in 1986. The SSS operates as a department within the presidency and is under the control of the National Security Adviser.

Directors General of the SSS
1. Colonel Abdullahi Mohammed(DG NSO)1976–1979 (October)

2. Alhaji Umaru Shinkafi(DG NSO)1979 (October) – 1983 (November)

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