Western embassies across the Muslim world remained on high alert on Sunday and the United States urged vigilance after days of anti-American violence provoked by a video mocking the Prophet Mohammad.

Germany followed the U.S. lead and withdrew some staff from its embassy in Sudan, which was stormed on Friday.

Washington ordered non-essential staff and family members to leave its embassy there on Saturday. But the Khartoum government turned down a U.S. request to send Marines to bolster security after the mission was attacked.

Non-essential U.S. personnel have also been withdrawn from Tunisia, and Washington urged U.S. citizens to leave the capital Tunis after the embassy there was targetted on Friday.

Although protests that peaked on Friday largely subsided over the weekend, a small group of protesters burned a U.S. flag outside the U.S. Embassy in the Turkish capital Anakara on Sunday.

Riot police blocked the road, keeping them about 100 metres (yards) from the building.

In the Paksitani city of Lahore, about 5,000 people gathered for a protest, chanting anti-U.S. slogans, while in Karachi, police blocked off roads to the U.S. consulate with shipping containers.

In Hyderabad, one person was killed and one wounded when unidentified gunmen opened fire at a protest against the film and in the capital of Pakistani Kashmir, Muzaffarabad, about 300 protestors burnt an effigy of U.S. President Barack Obama.

The Pakistan demonstrations were however generally small compared to previous bouts of unrest.

The violence is the most serious wave of anti-American protests in the Muslim world since the start of the Arab Spring revolts last year.

It was fanned by public anger over a video, posted on the Internet under several titles including Innocence of Muslims which mocked the Prophet Mohammad and portrayed him as a womaniser and a fool.

The US ambassador to Libya Christopher Stevens and three other Americans were killed in Benghazi, Libya, last Tuesday. At least nine people were killed in protests in several countries on Friday.

Some U.S. officials have suggested the Benghazi attack was planned by Islamist militants using the video as a pretext.

The crisis also presents Obama with a foreign policy headache as the campaign for the presidential election in November heats up.

WORST OVER?

US Defence Secretary Leon Panetta said he hoped the worst of the violence was over but that US missions must remain on guard against any flare-ups.

"There continue to be some demonstrations but it would appear that there is some levelling off on the violence that we thought might take place," Panetta told reporters on his plane en route to Asia on Saturday.

"Having said that these demonstrations are likely to continue over the next few days if not longer.

The United States had deployed a significant force in the Middle East to deal with any contingencies and rapid deployment teams were ready to respond to incidents, he said.

The foreign minister of Egypt, where hundreds of people were arrested after four days of clashes, assured US Secretary of State Hillary Clinton that U.S. diplomatic missions would be protected.

Mohamed Kamel Amr also told Clinton in a telephone call that the film was designed to incite racial hatred and was therefore 'contradictory with laws aimed at developing relationships of peace and mutual understanding between nations and states'.

In Los Angeles on Saturday, a California man convicted of bank fraud was taken in for questioning by officers investigating possible probation violations stemming from the making of the film. He has denied reports he was involved in the film's production,

In Lebanon, where one protester was killed in violence on Friday, Pope Benedict urged Arab leaders to work for peace.

"In a world where violence constantly leaves behind its grim trail of death and destruction, to serve justice and peace is urgently necessary," Benedict said at a mass on Beirut's Mediterranean seafront attended by 350,000 worshippers and leaders of Lebanon's Christian and Muslim communities.