Dakar, Senegal - On Sunday morning, Sani ibn Salihu went to pray for the dead. Even as he arrived at the central mosque of the Nigerian city of Jos to join a throng mourning 364 people whose bodies he said had already been taken there, the battered corpses kept coming: 11 in the hour he spent praying.
“There were women and children, old men,” among the bodies, Mr. Salihu, a peace activist and journalist, said in a telephone interview from Jos, the central Nigerian city where two days of ferocious violence between Christians and Muslims after a disputed local election has left hundreds of people dead.
A tense calm returned to Jos on Sunday as soldiers wrested control of the streets from armed Christian and Muslim gangs that had roamed the city, slaughtering people with guns and machetes and torching houses, churches, shops and cars, according to residents. The sudden and vociferous explosion of religious violence was the worst Nigeria has seen in at least four years.
Religious and health officials gave varying accounts of the death toll but agreed that at least 400 bodies had already been recovered and more probably remained in the charred churches, homes, cars and alleyways that had been no-go zones until Sunday. The Red Cross said that about 7,000 people had fled the most violent neighborhoods and that they were living in shelters.
The clashes began suddenly, taking the city by surprise in both the swiftness and ferocity of the bloodshed, despite a long history of religious violence in the region. The trouble began Friday as results of elections trickled in for important local government posts that control hundreds of thousands of dollars in government funds.
Elections have not been held in Jos for years, in part because of fears that the political parties would split along religious lines, which is in fact what happened. Even before the results were announced, gangs on both sides began rampaging, anticipating defeat. Christian gangs claimed that the governing party, the P.D.P., was being cheated of victory, while Muslim gangs claimed that the opposition A.N.P.P., which is identified largely with Muslims in the north, was being robbed of its win.
Nigeria’s 140 million people are about evenly divided between the Muslim and Christian faiths. People of both religions live all across the country, often cheek by jowl, usually in relative peace.
But the religious divide in this nation of more than 250 ethnic groups mirrors a geographical one, between a historically Muslim north and a Christian and animist south, as well as deep political divisions that cross religious lines. Beyond that there are conflicts over land and political power, which are often intertwined as a result of traditional customs that hold the rights of indigenous people over those of migrants from other parts of the country. Religion is almost always a proxy for those grievances.
The fissures are so profound that it takes only the smallest tremor for a seemingly peaceful community to descend into an abyss of bloodletting. In 2002, a dispute over a perceived insult to Islam during a beauty pageant led to riots in which hundreds died. In 2006, riots over Danish cartoons depicting the Prophet Muhammad led to the deaths of nearly 200 people in several Nigerian cities, more than in any other country that experienced violence in the global backlash against the cartoons.
Nigeria’s Middle Belt, a band of fertile land that straddles the largely Muslim north and the Christian south, has always been a hotbed of ethnic and religious violence, and Plateau State, of which Jos is the capital, has borne the brunt.
Most of the state’s original inhabitants come from tribes that are almost entirely Christian and animist, but the farmland and grazing pasture has attracted migrants for centuries, especially Muslim Hausa and Fulani people from the more arid north. In Jos, a picturesque city set on a verdant plateau in central Nigeria, 1,000 people died in religious riots in 2001, and in 2004 hundreds more were killed in a nearby city of Yelwa. Jos became a balkanized city, with Muslims and Christians retreating to separate neighborhoods.
Despite the history of religious bloodshed in the region, residents, officials and activists said the city had come a long way toward healing divisions. Interfaith commissions set up to improve relations between the faiths and ethnic groups after the 2001 riots appeared to help cool tensions. “Things had really improved in Jos,” said Nankin Bagudu, a Christian and state government commissioner who had worked with the League for Human Rights. “Nobody expected this kind of violence this time.”
Mr. Salihu, a Muslim, said that the violence threatened to undo years of careful bridge building between the communities.
“As someone who has been involved in a peace work between Christian and Muslims, this has set our work back 10 years,” he said. “It will take us a very long time to rebuild the confidence.”