Some human rights activists in Nigeria have criticised the decision by a former military ruler, Olusegun Obasanjo, to stand in next year's presidential election.

The veteran lawyer, Gani Fawehinmi, said General Obasanjo had clearly violated human rights while in office.

Another lawyer, Olisa Agbakoba, said Nigeria needed a fresh generation of politicians.

General Obasanjo, who ruled in the l970s, was the only military leader ever to have handed power voluntarily to a civilian government.