In the predominantly southern Christian city of Onitsha, residents and witnesses said at least six Muslims were beaten to death by Christian mobs which also burned two mosques there.
Tuesday's violence brought to 49 the total number of people killed in sectarian violence in Nigeria since Saturday, when protests over controversial cartoons published in Europe of the Prophet Muhammad turned violent in the northern Muslim city of Maiduguri for the first time, killing at least 18 people, police said.
Adamu Abubakar, secretary of the Red Cross in Bauchi, told reporters that similar protests broke out in Bauchi city soon afterward, leaving seven dead on Monday and another 18 dead on Tuesday.
Christian mobs burnt mosques in a southern Nigerian city and killing several people.
"The whole town is in a frenzy and people are running in all directions"
Resident of Onitsha
"The mosque at the main market has been burnt and I've counted at least six dead bodies on the streets," Izzy Uzor, an Onitsha resident and businessman, told the AP by telephone on Tuesday.
"The whole town is in a frenzy and people are running in all directions."
The violence appeared to be in reprisal for anti-Christian violence on Saturday in the mostly Muslim northern city of Maiduguri in which thousands of Muslims protesting against caricatures of the Prophet Muhammad attacked Christians and burned churches.
At least 18 people were killed.
Another Onitsha resident, Isotonu Achor, said one badly beaten Muslim man ran into his office from the streets to escape the violence.
"There is blood all over him and I'm scared they'll come for him here. If he doesn't get urgent treatment, he will die," Achor said.
Some cartoon protests have
Police and government officials were not immediately available for comment.
Nigeria, Africa's most populous country of more than 130 million people, is roughly divided between a predominantly Muslim north and a mainly Christian south.
Thousands of people have died in religious violence in Nigeria since 2000.
Saturday's protest over the controversial cartoons of the Prophet Muhammad in Maiduguri was the first violent demonstration over the issue in Nigeria.
Police say at least 18 people, most of them Christians, died, and 30 churches were burned down.
The Christian Association of Nigeria said at least 50 people were killed in the violence.
The cartoons, deemed blasphemous, first appeared in a Danish newspaper in September.