Beirut, Lebanon ? Thousands of Muslim protesters, enraged over the publication of caricatures of Islam’s prophet Muhammad, set ablaze the Danish Embassy on Sunday and rampaged through a predominantly Christian neighborhood, escalating sectarian tensions in a country whose melange of faiths can sometimes serve as a microcosm of the world’s religious divide.

The unrest was some of the worst in Lebanon in years, and leaders from across both political and religious spectra appealed for calm. In vain, some Muslim clerics tried to step into the hours-long fray to end the clashes, which news agencies said left at least one demonstrator dead and 30 wounded. In the streets, fistfights broke out between Christian and Muslim Lebanese after protesters threw rocks at a Maronite Catholic Church, broke windows at the Lebanese Red Cross office and shattered windshields of cars.

“Those who are committing these acts have nothing to do with Islam or with Lebanon,” Lebanese Prime Minister Fuad Siniora told Lebanon’s Future Television before the protests ended. “This is absolutely not the way we express our opinions.”

The unrest in Lebanon, mired in its own political uncertainty, was the latest turn in a controversy that has spread worldwide following publication of the cartoons in Denmark and other Western countries and showed no signs of ebbing Sunday. Demonstrators took to the streets in Afghanistan, Iraq, the West Bank and New Zealand. A day earlier, protesters burned the Danish and Norwegian embassies in Syria after charging past security barriers.

A demonstrator shouts slogans in front of the burning building housing the Danish mission in Beirut, Lebanon, during a protest against publication of caricatures of the Prophet Muhammad in European newspapers. Sunday's demonstration in Beirut spiraled out of control for several hours Sunday as thousands of Muslim protesters set fire to Denmark's mission and trashed the streets in a Christian neighborhood where it is located.

In Iraq, the Islamic Army in Iraq, a Sunni Arab insurgent group, issued an Internet statement calling for attacks on Danish companies and nationals. The group asked followers to “catch some Danish people and cut them into pieces.” There are about 500 Danish soldiers in Iraq, most based in the southern part of the country.

In their scope and vitriol, the protests say much about the state of relations between the West and the Muslim world in the wake of the Sept. 11, 2001, attacks in the United States. The anger was ignited by 12 caricatures of the prophet Muhammad that were commissioned in September by a Danish newspaper to challenge Islam’s ban on depicting the prophet. Along with picturing him, some lampooned him, with one artist rendering his turban as a bomb with a burning fuse. After protests began, other European papers reprinted the cartoons.

They declared it an issue of freedom of expression, a cornerstone of democratic values; many Muslims cast it as another insult in a growing conflict that is most often reflected here through the lens of a religious struggle with an American-led West.

“What are you going to do?” asked a leaflet circulated in Beirut that called for Sunday’s protest. “Bush and his group have invaded and are fighting war by all means available,” it added. “The goal: destroying the Islamic nation ideologically, economically and existentially, and stealing and looting its resources.”

The protest in Lebanon drew as many as 20,000 people answering calls from mosques Friday and similar leaflets circulated in Beirut and other cities. Most of them stayed peaceful. But bands broke through police lines at the Danish Embassy, and hundreds of protesters surged through nearby streets, waving green religious flags and shouting, “God is greatest.” Police shot into the air and fired tear gas and water cannons at protesters who threw stones, set ablaze fire trucks and overturned police vehicles. Dozens were arrested.

The Danish Embassy was gutted, and its granite facade scorched. Acrid black smoke spilled out of its windows hours later, as fire trucks tried to contain the blaze.

The Danish Foreign Ministry urged Danes on Sunday to leave Lebanon and instructed its citizens not to travel there. The embassy, bracing for the expected protests, had been evacuated Saturday. The building also housed the Austrian consulate.