Residents who have fled the violence are now living in refugee camps At least 80 people are now known to have died in violence around the Nigerian city of Jos in recent days.
Officials revised the death toll from about 40 after consulting hospitals.
Bombings struck mainly Christian areas of Jos on Christmas Eve, and Christian and Muslim youths clashed two days later. Security forces have been drafted in from neighbouring states.
Religious leaders have accused local politicians of using religion to stir up trouble between communities.
Jos has been a flashpoint for sectarian trouble in recent years.
Officials from Nigeria’s emergency management agency (Nema) said at least 80 people had died and more than 190 had been injured in the violence.
Ayo Oritsjafor, head of the Christian Association of Nigeria, said local politicians were trying to exploit religion to whip up trouble.
“I believe there are politicians in this country who know the weaknesses of our people,” he told the BBC.
“Some of them are creating these kind of problems to make Nigeria ungovernable.”
National and local elections are set for next April, and politicians are frequently accused of stirring up trouble to further their ambitions.
Meanwhile, a radical Muslim sect reportedly said they carried out the Christmas Eve bombings.
A website apparently belonging to the Boko Haram group, which staged an uprising in the city of north-eastern city of Maiduguri in 2008, said it launched the attacks to “start avenging the atrocities committed against Muslims”.
Deadly riots in 2001, 2008 and 2010City divided into Christian and Muslim areasHausa-speaking Muslims living in Jos for decades still classified as settlersSettlers find it difficult to stand for electionCommunities divided along political party linesJos violence: Q&A
But police chief Abdulrahman Akano cast doubt on the claims, saying it was not Boko Haram’s usual method.
“Anybody can post anything on the internet,” he told the AFP news agency.
Boko Haram members who took part in the 2008 uprising were armed mostly with sticks and home-made rifles.
Security forces put down the uprising and killed about 800 people, including the group’s leader.
Sultan Mohammadu Sa’ad Abubakar, the spiritual leader of Nigeria’s estimated 70 million Muslims, played down the Boko Haram link.
He called on all Nigerians “not to succumb to the moves and practices of the few destructive elements that really don’t want peace in this country”.
The city of Jos lies in Nigeria’s volatile Middle Belt – between the mainly Muslim north and largely Christian south.
Jos has been blighted by sectarian violence over the past decade, with deadly riots in 2001, 2008 and this year.
The clashes usually pit Muslims against Christians, but analysts say the underlying issues are political and economic.
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