By the time people begin to ask questions they will have themselves to blame

Commision chairman Justice Oputa

Justice Oputa said: "History, not the commission will pass judgment" on the leaders who ignored summonses to appear.

The three, Generals Ibrahim Babangida, Muhammadu Buhari and Abdulsalami Abubakar, had been asked to testify about killings, arbitrary jailings and the disappearance of millions of dollars of government funds.

Learn lessons

Mr Oputa added:" By the time people begin to ask questions , they will have themselves to blame."

He said his panel's job was to help Nigeria face the past truthfully and honestly, and learn lessons for the future.

Babangida: Snubbed rights panel

Only Nigeria's President Olusegun Obasanjo, who was a military ruler in the late 1970s, appeared before the commission.

He had gone to answer charges by the family of the late afro music king Fela Ransome-Kuti, that he was involved in the 1979 army raid that lead to the death of the musician's mother.

But Mr Obasanjo in his testimony on 11 September denied any wrong-doing, and said he had decided to give evidence "to set an example" over the rule of law.

Ken Saro-Wiwa

Before that in 2000, Mr Obasanjo had petitioned the courts over his detention for three years on false charges.

The panel travelled around the country and took evidence from among those who had submitted some 11,000 memoranda detailing alleged human rights abuses.

Abubakar: Criticised by the media for not testifying

Other high profile hearings included army atrocities during the Biafran war in the 1960s and the execution in 1995 of Ken Saro-Wiwa the environmental campaigner and poet.

The circumstances surrounding the death of the presumed winner of the 1993 elections in Nigeria, Moshood Abiola were also investigated.

The French news agency,AFP, reports that Justice Oputa in September had accused some of those who testified of simply lying.