[1][2] Aksentijević was one of the few senior Yugoslav army officers to be involved in all three of the wars in Slovenia, Croatia, and Bosnia during the break-up of Yugoslavia.
In 1953, he graduated from the School for Active Engineering and Chemical Officers of the Yugoslav People's Army (JNA).
Aksentijević graduated from the Vuša Military Academy and the School of National Defense, as well as postgraduate studies there.
Interviewed for the BBC documentary The Death of Yugoslavia he recalled angrily asking for orders from JNA high command, asking "Are we an army or not?
[8] From July 1991 to 31 December 1991, Aksentijević was the Assistant Commander of the 5th Military District of the Armed Forces of the SFRY for Moral Education and Legal Affairs.
Whilst in Bosnia Aksentijevic was the chief negotiator with the Vice President of the Presidency of Bosnia and Herzegovina (BiH), Ejup Ganic, on the release of Alija Izetbegovic and the events that surrounding the showdown in Dobrovoljacka Street in Sarajevo on 3 May 1992.
[10] In January 1992 Aksentijević was stripped of Slovene citizenship due to his role in the Ten Day War.