An elite team of Marines have arrived in Yemen's capital as violent protests rage at the U.S. Embassy over the depiction of the Prophet Muhammad in an American-made film.

Pentagon press secretary George Little said the decision to dispatch about 50 Marines to Sanaa was partly in response to the violence and partly as a precautionary measure. Angry demonstrators attacked the U.S. Embassy in Sanaa on Thursday, breaching the compound and burning an American flag. Protests continued on Friday.

A U.S. official on Friday night said Marines were also headed to Sudan. The official spoke on condition of anonymity because the deployment was not made public.

Renewed protests and deadly riots escalated Friday in parts of the Middle East, North Africa and Southeast Asia over a highly provocative and offensive film depicting the Prophet Muhammad. Muslims staged protests, many of them peaceful, in more than 20 countries, including Sudan, Lebanon, Tunisia, Iraq, Pakistan, Malaysia and Niger.

However, U.S. diplomatic missions remained on high alert in many countries following Tuesday night’s assault on the American consulate in Benghazi, Libya, where U.S. Ambassador Chris Stevens and three other Americans were killed.

In Lebanon, security officials said a crowd in Tripoli set fire Friday to a KFC and an Arby's restaurant. In a clash with security forces, one protester was killed and 25 people were wounded, including 18 police.

In Sudan, witnesses said that police opened fire on protesters trying to scale the walls of the U.S. Embassy in Khartoum, the Associated Press reported. The witnesses said at least three protesters were seen motionless after the shooting, but there was no immediate confirmation on their condition.

Earlier in Khartoum, hundreds stormed past the gates of the German Embassy, burning a car and trash cans before police fired tear gas to repel the protesters.

A prominent cleric had urged people on state radio to protest outside the main mosque in Khartoum. Sheikh Mohammed Jizouly directed protesters to the German Embassy in the city centre to protest alleged anti-Muslim scrawling on mosques in Berlin and then to the U.S. Embassy, just outside the capital, to protest the film.

"America has long been an enemy to Islam and to Sudan," Jizouly said.

In Tunisia, thousands of demonstrators gathered outside the U.S. Embassy. Some protesters scaled the walls of the embassy, where they broke windows, set fires and planted an Islamic banner. Police fired rounds in the air and used tear gas to repel the protesters.

Protesters also set fire to an American school adjacent to the embassy compound and prevented firefighters from approaching it. Thick columns of black smoke wafted through the neighbourhood.

Tunisia's official news agency says the protest in Tunis left three demonstrators dead and 28 people injured, both protesters and police officers.

Continued clashes in Cairo

Shia Muslim supporters of the Imamia Student Organization shout slogans as they burn a U.S. flag during a demonstration in Peshawar, Pakistan, on Friday. (Fayaz Aziz/Reuters )

The CBC’s Derek Stoffel reported earlier Friday from central Cairo that scuffles continue between rock-throwing protesters and riot police who respond with tear gas to push the crowds back.

“These are young men, boys in many cases, and some Egyptians tell me they’re just troublemakers who have nothing better to do than taunt police,” said Stoffel.

Few among the crowd are religious people or women, "quite a difference from what I saw during the Arab Spring protests in Tahrir Square," said Stoffel.

Earlier in the day, Egyptian security forces geared up for more possible confrontations after Friday prayers, which has been a traditional time of protest in Africa and the Mideast. A concrete wall was constructed to keep protesters away from the U.S. Embassy.

A morgue official told AP that an Egyptian protester had been killed in clashes with police near the embassy. The official said the 20-year-old died from wounds suffered Friday from rubber bullets.

Islamist President Mohammed Morsi spoke for more than seven minutes on state TV in a move to contain protests.

"It is required by our religion to protect our guests and their homes and places of work," Morsi said. "So I call on all to consider this, consider the law, and not attack embassies, consulates, diplomatic missions or Egyptian property that is private or public."

Morsi's own Muslim Brotherhood group has called for peaceful protests to denounce the film.

The CBC’s Sasa Petricic in Cairo reported earlier Friday that some critics are finding the moderate comments of the Muslim Brotherhood interesting, “because it was groups like these that were partly responsible for riling up the crowd in the first place. Now they are trying to put the genie back in the bottle,” he said. "It’s very much out of their control. This has taken a life of its own."

The Canadian Embassy, which is on the same street as the U.S. Embassy, will remain closed until at least Sunday.

Renewed protest in Yemen

Security forces in Yemen shot live rounds in the air and fired a water cannon and tear gas at a crowd of around 2,000 protesters trying to march to the U.S. Embassy in the capital Sanaa.

Friday's protest comes a day after hundreds of protesters chanting "death to America" stormed the embassy compound and burned the American flag. The embassy said nobody was harmed.

Yemen's president, Abed Rabbo Mansour Hadi, quickly apologized to the United States and vowed to track down the culprits.

On Friday, protesters in Sanaa outnumbered police but security forces were able to keep the crowd about a block away from the embassy by afternoon.

The Marines that arrived in the Yemeni capital Friday are members of a platoon from a Fleet Antiterrorism Security Team, a specially trained and configured group that makes short-notice deployments in response to terrorist threats and to reinforce security at U.S. embassies.

A similar team was dispatched to Tripoli, Libya, on Wednesday in response to the deadly consulate attack in Benghazi.

Pentagon press secretary George Little said no other such teams had been sent to Cairo or other Arab capitals.

In Pakistan, some Muslims held peaceful protests against the film, shouting slogans and carrying banners. Police in Islamabad set up barricades and razor wire to prevent protesters from getting to the diplomatic enclave, where the U.S. Embassy and many other foreign missions are located.

In East Jerusalem, Israeli police stopped a crowd of around 400 Palestinians from marching on the U.S. Consulate. Demonstrators threw bottles and stones at police, who responded with stun grenades. Four protesters were arrested.

Protesters also attacked a Christian school in eastern Niger, destroying a statue of the Virgin Mary, the AP reported. The mob burned the school's door and bunks used by the pupils before security forces intervened.

A small, peaceful demonstration was held Friday outside the U.S. Embassy in the Malaysian capital, Kuala Lumpur.

U.S. rejects message of video, but also violence

Speaking in Washington, D.C., on Thursday, U.S. Secretary of State Hillary Clinton called the video "disgusting and reprehensible."

"The United States government had absolutely nothing to do with this video. We absolutely reject its content and message," said Clinton.

"Our country does have a long tradition of free expression, which is enshrined in our constitution and in our law. We do not stop individual citizens from expressing their views no matter how distasteful they may be. There are of course different views around the world about the outer limits of free speech and free expression. But there should be no debate about the simple proposition that violence in response to speech is not acceptable.”

Prime Minister Stephen Harper also denounced the ongoing violence in the Middle East and North Africa and expressed concern for diplomats in the region.

"As I've said before, our diplomatic personnel are not military. They're not paid to put their lives on the line," Harper said Friday, speaking from Fort Lennox in Quebec.

Meanwhile, a Libyan airport official said all flights to and from the eastern city of Benghazi were cancelled because of security concerns. The nearest airport is 200 kilometres away. The airport official spoke on condition of anonymity because he was not authorized to release the information.

With files from The Associated Press