LAGOS, Nigeria (AP) _ Nigerians convicted in an alleged plot to overthrow the government say they were tortured and that the evidence against them was false, newspapers reported.

Notes apparently written by some of the convicts and smuggled out of prison were published Thursday in several Lagos newspapers.

One note was reportedly written by former military ruler Gen. Olusegun Obasanjo just before he was moved to the Jos Prison in central Nigeria at dawn Wednesday to begin a 15-year jail term. The note said that some prisoners were tortured into confessions ``almost to the point of death,'' but did not give details.

Obasanjo described the case as a ``naked frame-up'' by the military government.

The government would not comment on the published letters.

Obasanjo was one of 41 civilians and military officials convicted in a secret military tribunal in July of plotting a coup against Gen. Sani Abacha. Thirteen of them were given death sentences and many others, including Obasanjo, were sentenced to life terms.

International pressure prompted Abacha to commute the death sentences to life in prison and to reduce many of the prison terms, including Obasanjo's.

Obasanjo, 59, was Nigeria's head of state from 1976 to 1979 and is the only military ruler in the country's history to voluntarily hand power to a civilian government. He has urged Abacha to do the same.

Notes were also smuggled out of jail from Beko Ransome-Kutu, leader of the Campaign for Democracy opposition group, and Malam Shehu Sani, the group's vice president. Both also are serving 15-year terms for their alleged involvement in the coup plot.

``Details of the government's case ... are just too fantastic to make sense,'' read the note signed by both men.