Angry protests over an anti-Islam film spread across the Muslim world today, with demonstrators scaling the walls of US embassies in Tunisia and Sudan and torching part of a German embassy.
Amid the turmoil, Islamic militants waving black banners and shouting "God is great" stormed an international peacekeepers base in Egypt's Sinai and battled troops, wounding four Colombians.
Egypt's new Islamist president went on national TV and appealed to Muslims to not attack embassies, denouncing the violence earlier this week in Libya that killed four Americans, including the US ambassador.
Mohammed Morsi's first public move to restrain protesters after days of near silence appeared aimed at repairing strains with the United States over this week's violence.
Throughout the region, security forces struggled to rein in protesters. Police in Cairo prevented stone-throwing demonstrators from nearing the US Embassy, firing tear gas and deploying armoured vehicles in a fourth day of clashes in the Egyptian capital. At least three protesters were killed around the region.
The day of protests, which spread to around 20 countries, started small and mostly peacefully in countries such as Indonesia, Malaysia, India, Afghanistan and Pakistan.
The most violent demonstrations took place in the Middle East. In many places, only a few hundred took to the streets, mostly ultraconservative Islamists - but the mood was often furious.
The demonstrators came out after weekly Friday Muslim prayers, where many clerics in their mosque sermons urged congregations to defend their faith, denouncing the obscure movie produced in the US that denigrated the Prophet Mohammed. It was a dramatic expansion of protests that began earlier this week and saw assaults on the US embassies in Egypt and Yemen and the storming of the US Consulate in Benghazi, Libya.
Several thousand battled with Tunisian security forces outside the US Embassy in Tunis. Protesters rained down stones on police firing volleys of tear gas and shooting into the air. Some protesters scaled the embassy wall and stood on top of it, planting the Islamist flag that has become a symbol of the wave of protests.
Two protesters were killed and 29 people were wounded, including police.
The heaviest violence came in Sudan, where a prominent sheikh on state radio urged protesters to march on the German Embassy to protest alleged anti-Muslim graffiti on mosques in Berlin and then to the US Embassy to protest the film.
"America has long been an enemy to Islam and to Sudan," Sheik Mohammed Jizouly said.
Soon after, several hundred Sudanese stormed into the German Embassy, setting part of an embassy building aflame along with trash bins and a parked car. Some then began to demonstrate outside the neighbouring British Embassy, shouting slogans.
Several thousand then moved on the American Embassy, on the capital's outskirts. They tried to storm the mission, clashing with Sudanese police, who opened fire on some who tried to scale the compound's wall.
The police then launched giant volleys of tear gas to disperse the crowd, starting a stampede. Witnesses reported seeing three protesters motionless on the ground, apparently dead, though there was no immediate confirmation of deaths in the violence.
The attack on the peacekeepers base in Egypt's Sinai Peninsula raised the dangerous prospect of armed Islamic militants exploiting the turmoil to carry out attacks on Western targets. The base near the border with Gaza and Israel houses some 1,500 members of the multinational force, including American troops.
Gunmen stormed into the base, firing automatic weapons. They set fire to vehicles and battled with peacekeepers inside, said a senior official with the force. Four Colombian peacekeepers were wounded and were evacuated to Israel.
Ahead of the expected wave of protests today - a traditional day for rallies in the Islamic world - US Secretary of State Hillary Rodham Clinton explicitly denounced the movie, aiming to pre-empt further turmoil at its embassies and consulates. The film, called "Innocence of Muslims," ridicules the Prophet Mohammed, portraying him as a fraud, a womaniser and a child molester.
In his TV address Morsi said that "it is required by our religion to protect our guests and their homes and places of work," he said.
He called the killing of the American ambassador in Libya unacceptable in Islam.
His speech came after President Barack Obama spoke with Morsi by telephone. The Obama administration has been angered by Morsi's slow response to the attack on the US Embassy in Cairo.