The bodies of at least 150 victims have been pulled from wells after the recent clash between Christians and Muslims in the central Nigerian city of Jos.
Muhammad Tanko Shittu, a Muslim official involved in helping gather and bury the bodies, said more bodies are still being found.
Human Rights Watch said Saturday that some of the victims had been burned alive.
The death toll is already estimated at more than 200 from four days of violence in which roving gangs armed with guns, machetes and knives attacked hundreds of people.
The Red Cross said at least 17,000 people took shelter in schools, military barracks and hospitals, and thousands remain there.
The violence began on Sunday for reasons that remain unclear. Jos has a history of religious tension, and this is the fourth major burst of Muslim-Christian violence in the city in the past decade.
Police Minister Ibrahim Yakubu Lame blamed the latest clashes on unnamed "highly placed individuals" who he said are exploiting people's ignorance and poverty in the name of religion.
The U.S. Embassy in Nigeria has urged the government to prosecute all those responsible for the Jos violence.
Previous outbreaks killed at least 200 people in 2008, 700 people in 2004 and 1,000 people in 2001.
Some information for this report was provided by AFP and Reuters.
