 In 1967, he fought during the Nigerian Civil War.He was Commander of 9 Infantry Brigade, Abeokuta (April 1976 – July 1978), Adjutant General of 2 Mechanised Division (July 1978 – September 1979) and Director of Personnel Services, Army Headquarters (October 1979 – November 1979).From November 1979 to December 1983, Aliyu was Director of Military Intelligence (DMI).