Barnaby Phillips in Warri: Nigerians are surprised by the speed and extent of the purge

About 30 senior military officers have been forcibly retired and the purge is moving into the next echelon of senior officers.

Casualties include two former commanders of the West African peacekeeping force in Sierra Leone and Liberia.

President Obasanjo is expected to remove officers who held political appointments either as state governors or cabinet ministers in previous regimes, and who may still be ambitious enough to try to seize power.

Those affected by the shake-up include Mohammed Abdallah, the former military chief of staff under General Sani Abacha, whose strong-armed rule turned Nigeria into an international pariah and held up democratic reforms until his death 12 months ago.

War on corruption

The BBC's Simon Jones: The purge looks likely to continue

The authorities have also seized hundreds of millions of dollars allegedly stolen from the state during General Abacha's rule.

Most of Nigeria's revenue was paid into private bank accounts before the return to democracy, and senior members of successive military administrations amassed fortunes amounting to billions of dollars.

As a former general President Obasanjo knows the military well

According to Nigerian state TV, included is the immediate seizure of more than $420m in a petroleum refinery, including $140m held by a former national security official.

President Olusegun Obasanjo took office last month saying he wanted a new war on corruption.

He replaced the heads of the army, navy and airforce on his first day in office.

And within days, the newly-elected civilian president sacked allegedly corrupt customs officials and suspended contracts signed by the previous military government.

He also set up a panel to scrutinise all new projects, including lucrative oil concessions.

Nigeria has been ruled for all but 10 of the last 29 years by military governments.

Nigerian political analyst Ibrahim Adamu said that for the Nigerian military to stick to their constitutional role and keep out of government, a major reorganisation and reorientation is imperative