LAGOS, Nigeria -- President Olusegun Obasanjo declared a state of emergency in a troubled central state yesterday, invoking sweeping powers in a bid to halt religious and ethnic bloodletting that he said posed a ''great threat" to national unity.
Obasanjo sacked Governor Joshua Dariye and dissolved the Legislature in the central state of Plateau, saying elected officials had ''wittingly and unwittingly encouraged acts that have subverted peace and tranquility."
The declaration -- made in an address on national radio and television -- came after months of violence in the state of hilly farms and pastures.
Retired Major General Chris Ali, who served in the Nigerian Army under previous junta rulers, will replace Dariye.
Dariye's spokesman, Stanley Bentu, said the governor accepted Obasanjo's declaration.
It was Obasanjo's first emergency declaration, giving him the ability to govern by decree, since his 1999 election ended 15 years of repressive military rule. Since then, intertwined ethnic, political, and religious violence has left more than 10,000 dead across Africa's most populous nation.
The move lets Obasanjo govern the state without consulting other officials or the national Legislature. Plateau already is patrolled by heavily armed police and soldiers, recently accused by New York-based Human Rights Watch of carrying out indiscriminate killings.
Attacks against Muslims by Christian ethnic groups in Plateau killed hundreds this month, sent tens of thousands of refugees fleeing, and prompted mob revenge attacks against Christians in Kano state, where scores more died.
Resurgent fighting in Plateau ''constitutes a grave threat to law and order and a great danger to security in Plateau state and neighboring states," Obasanjo said. ''It is therefore clearly a great threat to the security and unity of Nigeria."
Fighting has plagued Plateau since September 2001, when more than 1,000 were killed in the previously tranquil city of Jos, 210 miles northeast of the capital, Abuja.
Bloodshed surged again this month with the killings of hundreds of Hausa-speaking Muslims by members of a Christian Tarok-speaking ethnic militia in the Plateau town of Yelwa.
Violence spread last week as Muslim Hausas rioted in the northern city of Kano, attacking Christians and killing scores in apparent revenge for the Yelwa slayings.
''We need to take serious steps to stem the tide of what has become a near-mutual genocide in the affected areas of Plateau state," Obasanjo said. ''In my personal and official capacities, I have done everything to bring lasting peace to Plateau state."
Christian and Muslim groups had both accused Dariye of siding against them in the violence. However, Obasanjo's declaration pleased neither group as religious leaders and human rights activists accused Obasanjo of overstepping his presidential powers.
Saidu Dogo, a regional official of Nigeria's main Christian umbrella group in the northern city of Kaduna, accused Obasanjo of making Plateau's Christian-led government a scapegoat.
Lateef Adegbite, secretary-general of Nigeria's Supreme Council for Islamic Affairs, said he approved of the emergency powers but disagreed with the appointment of a general, citing Muslim fears that Obasanjo, himself a former general, was ''militarizing the country."
Gani Fawehinmi, a human rights campaigner, argued Obasanjo had ''no right" under the 1999 constitution to dismiss state officials.
''What Obasanjo has done portends great danger for our democracy and will scare away foreign investors," Fawehinmi said. ''The sustenance of our democracy is hanging in the balance."
Obasanjo did not say whether yesterday's emergency declaration was linked to a recent security force investigation of unspecified ''security breaches" that some army commanders described as a plot by army officers and civilian collaborators to topple the president in a coup.
The ''security breaches" prompted government officials to disallow antigovernment demonstrations, with the president's spokeswoman Remi Oyo at one point saying any protester would be considered an ''enemy of the state."
Obasanjo, 66, is a former general who in 1979 became Nigeria's first junta leader to voluntarily step aside. He returned to politics two decades later as an elected civilian. He was reelected last year in a vote rejected as rigged by his main opponent, former military ruler Muhammadu Buhari.