MAIDUGURI, Nigeria - Nigerian Muslims protesting caricatures of the Prophet Muhammad attacked Christians and burned churches on Saturday, killing at least 15 people in the deadliest confrontation yet in the whirlwind of Muslim anger over the drawings.
It was the first major protest to erupt over the issue in Africa's most populous nation. An Associated Press reporter saw mobs of Muslim protesters swarm through the city center with machetes, sticks and iron rods. One group threw a tire around a man, poured gas on him and set him ablaze.
In Libya, the parliament suspended the interior minister after at least 11 people died when his security forces attacked rioters who torched the Italian consulate in Benghazi.
Right-wing Italian Reforms Minister Roberto Calderoli resigned under pressure, accused of fueling the fury in Benghazi by wearing a T-shirt emblazoned with one of the offending cartoons, first published in September in a Danish newspaper.
Danish church officials met with a top Muslim cleric in Cairo, meanwhile, but made no significant headway in defusing the conflict.
And in what has become a daily event, tens of thousands of Muslims protested - this time in Britain, Pakistan and Austria - to denounce the perceived insult. On Sunday, some 400 protesters pelted the U.S. Embassy in Indonesia with rocks, tomatoes and eggs. They burned U.S. flags and smashed the windows of a guard post before dispersing.
But it was in Nigeria, where mutual suspicions between Christians and Muslims have led to thousands of deaths in recent years, that tensions boiled over into sectarian violence.
Thousands of rioters burned 15 churches in Maiduguri in a three-hour rampage before troops and police reinforcements restored order, Nigerian police spokesman Haz Iwendi said. Iwendi said security forces arrested dozens of people in the city about 1,000 miles northeast of the capital, Lagos.
Chima Ezeoke, a Christian Maiduguri resident, said protesters attacked and looted shops owned by minority Christians, most of them with origins in the country's south.
"Most of the dead were Christians beaten to death on the streets by the rioters," Ezeoke said. Witnesses said three children and a priest were among those killed.
The Danish cartoons, including one showing Muhammad wearing a bomb-shaped turban with an ignited fuse, have set off sometimes violent protests around the world.
After the Danish newspaper Jyllands-Posten printed the caricatures in September, other Western newspapers, mostly in Europe, followed suit, asserting their news value and the right to freedom of expression.
But Nigeria has been spared much of the violence seen elsewhere in the world, though lawmakers in the heavily Muslim state of Kano burned Danish and Norwegian flags and barred Danish companies from bidding on a major construction project. Kano lawmakers also called on the state's 5 million people to boycott Danish goods.
Nigeria, with a population of more than 130 million, is roughly divided between a predominantly Muslim north and a mainly Christian south.
With Saturday's deaths, at least 45 people have been killed in protests across the Muslim world, according to a count by The Associated Press.
In the violence in Libya, Seif el-Islam Gadhafi, the son of Libyan leader Moammar Gadhafi, said four of the 11 dead were believed to have been Egyptians or Palestinians.
"Setting the consulate on fire was a mistake, but using excessive force was the most tragic response," the younger Gadhafi said, explaining the suspension of Interior Minister Nasr al-Mabrouk.
Italian Premier Silvio Berlusconi blamed the riots in Libya, Italy's former colony, on "thoughtless action by our minister," the Italian news agency ANSA quoted him as saying.
Calderoli said he wore the shirt to show "solidarity to all those who were hit by the blind violence of religious fanaticism." He said he did not intend "to offend the Muslim religion nor to be the pretext for yesterday's violence."
At the U.S.-Islamic World Forum in Doha, Qatar, U.S. Undersecretary of State Karen Hughes said U.S. newspapers generally did not reprint the caricatures "because they recognize they are deeply offensive, even blasphemous to the precious convictions of our Muslim friends and neighbors."
In Cairo, Bishop Karsten Nissen, of Denmark's Evangelical Lutheran Church, met with Grand Imam Mohammed Sayyed Tantawi of al-Azhar University, the world's highest Sunni Muslim seat of learning.
Tantawi said the Danish prime minister must apologize for the drawings and further demanded that the world's religious leaders meet to write a law that "condemns insulting any religion, including the Holy Scriptures and the prophets." He said the United Nations should impose the law on all countries.
In response, Nissen did not address the issue of a global law but said it was impossible for Prime Minister Anders Fogh Rasmussen to apologize.
"I have brought to his excellency (Tantawi) the apology of the newspaper, but our prime minister did not draw these cartoons. Our prime minister is not the editor of this newspaper. He cannot apologize for something he did not do," Nissen said.
In Pakistan on Sunday, police raided offices and homes of dozens of radical Islamic leaders, putting several under house arrest and detaining hundreds of their associates to foil a rally in the capital, officials said.
So far the West and Islamic nations remain at loggerheads over fundamental, but conflicting cultural imperatives - the Western democratic assertion of a right to free speech and press freedom, versus the Islamic dictum against any representation of the Prophet Muhammad. Muslims say such depictions could encourage idolatry.