Nigerian President Olusegun Obasanjo has announced a major shake-up of his country's military.
Mr Obasanjo said he had been maligned in the press
The chiefs of the defence staff and air-force have been dismissed, along with the national security adviser.
The army chief has been promoted to chief of defence staff. No reasons have been given for the decisions.
Since independence in 1960, Nigeria has had many years of military rule. Political tension is rising ahead of elections due next year.
Mr Obasanjo, a former military ruler who won multiparty elections in 1999, recently said he would not seek re-election, after attempts to change the constitution to let him seek a third term in office were defeated.
Political observers suggest the removal of national security advisor Gen Aliyu Mohammed Gusau may be the most significant change, since he had recently been mentioned as a possible successor to the Nigerian president.
- Gen Gusau is replaced by Maj Gen Sarki Muktar.
- The chief of defence staff, Gen Alexander Ogomudia, is replaced by army chief Lt Martin Luther Agwai
- Air Marshal Jonah Domfa Wuyep is replaced by Air Vice Marshal Paul Dike as Chief of Air Staff
- Maj Gen Owoye Andrew Azazi replaces Lt Agwai as chief of Army Staff.