NATIONAL NEWS (CNN) — United States embassies and consulates across the Middle East kept security forces at the ready Friday as Muslims protested across the region, enraged by an online movie trailer that characterizes the Prophet Mohammed as a womanizing buffoon.
"We are in a full-court press at every single one of the posts in the Middle East and anywhere else there is any chance of demonstrations after Friday services to make sure nothing bad happens -- and to have the security in place in case bad things do happen," one senior administration official said Thursday.
The official, who was not authorized to discuss the issue in public, spoke on condition of anonymity.
A running battle between police and protesters in Cairo continued into its fourth day Friday, while Afghanistan saw its first demonstrations of the current wave of unrest, security forces fired on crowds in Yemen, and hundreds chanted "No to America, no to Israel" in Iraq.
Israeli security forces clashed with hundreds of Palestinian demonstrators chanting anti-American and anti-Israeli slogans in Jerusalem.
And up to 10,000 demonstrators converged on the German Embassy in Khartoum, Sudan, and set it on fire, a journalist on the scene said. Some managed to get inside and pull down a German flag before police with tear gas forced the crowds to retreat.
The German mission is next to the British Embassy, which is also facing protests, staff there said.
Egypt's influential and well-organized Muslim Brotherhood canceled nationwide protests planned for Friday, it announced on Twitter, but said a demonstration planned for Cairo's Tahrir Square will go ahead.
Fifteen people have been injured in demonstrations in Egypt on Friday, Health Ministry spokesman Mohamed Sultan said.
As word of video spreads, so do protests
The film that sparked the protests is a 14-minute trailer that mocks Mohammed as a womanizer, child molester and ruthless killer.
Generating little interest when it was first posted in July on YouTube, the clip received global attention after it was aired on Egyptian television and anti-Islam activists promoted it online.
People have taken to the streets in at least 12 nations and territories to show their outrage about the film.
On Tuesday, the U.S. Consulate in Benghazi was attacked, leading to the deaths of U.S. Ambassador Chris Stevens, State Department computer expert Sean Smith, and security officers Glen Doherty and Tyrone Woods, both former Navy SEALs.
The film permit for "Innocence of Muslims" has been withdrawn at the request of U.S. authorities, who cited public safety concerns, according to Film LA Inc., the nonprofit agency that oversees production in the Los Angeles area.
Withdrawing the permit means the agency cannot release copies of the film.
YouTube has restricted access to the video.
Federal authorities have discounted as false a producer's claims to news outlets that he was an Israeli who made the movie with financing with help from more than 100 Jewish donors. Israel's government denies that the film's backer is Israeli.
The protests across the Islamic world, and the false claim by the producer about Jewish donors, caused the FBI and Department of Homeland Security to warn in a joint bulletin of a risk of an increase in violence "at home and abroad as the film continues to gain attention."
Unrest in Egypt
Outside the U.S. Embassy in Cairo, riot police sporadically clashed with protesters for a fourth straight day after a failed attempt to disperse the demonstrators shortly after dawn Friday.
Police armed with shields and batons, backed by an armored personnel carrier, rushed a group of several hundred protesters. The move came after U.S. President Barack Obama warned that relations with Egypt will be shaped by how the country responds to the violence.
"I don't think that we would consider them an ally, but we don't consider them an enemy," Obama told Telemundo in an interview that aired Thursday night.
The president issued a clear warning that Egypt needed to protect American diplomatic facilities in the country.
If Egypt takes actions that "indicate they're not taking responsibilities, as all other countries do where we have embassies, I think that's going to be a real big problem," he said.
Authorities have arrested 37 people in connection with the violence, according to Egypt's state-run news agency.
A seesaw battle that began Thursday between protesters and police raged through most of the night, with demonstrators throwing Molotov cocktails and rocks, and authorities responding with tear gas.
Sporadic gunfire could be heard around the U.S. Embassy.
At least 224 people were injured, according to Egyptian state television, Nile TV. Among the injured were 31 police officers, according to the Ministry of the Interior.
Protests across a dozen countries
Other countries across the region also saw protests and threats of demonstrations.
Afghanistan saw its first anti-American protest over the film Friday, as hundreds of demonstrators burned a U.S. flag and chanted "Death to America" and "We condemn the film."
The demonstration in Nangarhar province lasted about an hour and ended peacefully, said Zia Abdulzai, a spokesman for the governor of the eastern province.
The Afghan government has ordered an indefinite block of YouTube to prevent people there from watching the clips and staging violent protests.
In Baghdad, Iraq, hundreds of followers of the radical Shiite Muslim cleric Muqtada al-Sadr chanted slogans.
Palestinians marched from the al-Aqsa mosque overlooking Jerusalem toward the U.S. Consulate, but were prevented from reaching the mission by Israeli riot forces.
In Syria, hundreds gathered outside the U.S. Embassy in Damascus. Protesters waved placards that condemned the film and blamed the U.S. administration for allowing the production and broadcast of it, according to the state-run Syrian Arab News Agency.
In Iran, the Islamic Propagation Coordination Council called for nationwide rallies Friday to protest the film and what it is calling a U.S.-backed plot against Muslims, according to the state-run IRNA news agency.
Four arrested in Libya
Sources tracking militant Islamist groups in eastern Libya say the attack that killed Stevens and three other Americans was most likely carried out by a pro-al Qaeda group. Obama has vowed "justice will be done."
The first of two U.S. warships, carrying guided missiles, has arrived off the coast of Libya, and unmanned drones have been sent to help search for the killers.
A group of Marines called a Fleet Antiterrorism Security Team was deployed to Libya to help secure U.S. facilities, said two U.S. officials, who spoke on condition of anonymity because they were not authorized to release the information.
About 50 Marines arrived in the country Wednesday, the officials said.
Four people have been arrested in connection with the attack on the U.S. Consulate in Benghazi that left Stevens and the three other Americans dead, the president of the parliament's top aide said.
Those arrested were not directly tied to the attacks that killed Stevens and the others, said Monem Elyasser, the chief aide.
Elyasser did not release the identities nor did he detail the allegations against the four people in custody.
During an interview with CNNI's Christiane Amanpour on Thursday, Prime Minister Mustafa Abushagur said there had been one arrest earlier in the day in Benghazi and three or four others who were being pursed.
"The evidence itself is based on mostly pictures that were taken around the compound at that time and also through some witnesses," he said.
CNN's Kareem Khadder, Mohammed Tawfeeq, Arwa Damon, Ben Wedeman, Hamdi Alkhshali, Brian Walker and Elise Labott, and journalists Masoud Popalzai and Isma'il Kamal Kushkush contributed to this report.