TRIPOLI: Libya's parliament chief announced on Sunday the arrests of some 50 people over the killing of US ambassador Chris Stevens in an attack he said was planned, although Washington said it was spontaneous.
US Defence Secretary Leon Panetta, meanwhile, said the American military has no major plans to bolster its forces in the Middle East despite a week of violent protests targeting diplomatic outposts, including at the US consulate in Libya's eastern city of Benghazi where Stevens died.
"The number reached about 50," Mohammed al-Megaryef, president of the Libyan National Congress, said in an interview with CBS News.
Stevens and three other Americans were killed on Tuesday when suspected Islamic militants fired on the US consulate in Benghazi with rocket-propelled grenades and set it ablaze.
Megaryef said "a few" of those who joined in the attack were foreigners who had entered Libya "from different directions, some of them definitely from Mali and Algeria."
"The others are affiliates and maybe sympathisers," he added.
Megaryef said the government has learned the attack was not the result of spontaneous anger over a US-made anti-Islam movie which has triggered sometimes deadly protests across the Arab and Muslim world.
"It was planned, definitely, it was planned by foreigners, by people who entered the country a few months ago. And they were planning this criminal act since their arrival," he told CBS.
But Washington's ambassador to the United Nations, Susan Rice, offered a very different account, saying the assault began with a "spontaneous" protest over the video.
"Our current best assessment, based on the information that we have at present, is that, in fact, what this began as, it was a spontaneous -- not a premeditated -- response to what had transpired in Cairo," Rice said.
"We believe that folks in Benghazi, a small number of people came to the consulate to replicate the sort of challenge that was posed in Cairo," she told ABC's "This Week" programme.
"And then as that unfolded, it seems to have been hijacked, let us say, by some individual clusters of extremists who came with heavier weapons. And it then evolved from there."
Al-Qaeda in the Arabian Peninsula (AQAP) has said in a statement the attack was revenge for the killing of the terror network's deputy leader Sheikh Abu Yahya al-Libi in a drone strike in June, and called for more attacks on US targets.
US officials have already deployed counter-terrorism Marine units to Libya and Yemen and stationed two destroyers off the North African coast.
Panetta told reporters before arriving in Tokyo that with a substantial force already deployed in the region and now boosted by extra Marine units, the military has the ability to respond as necessary to protect American diplomats.
"We do have a major presence in the region," he said.
"Having said that we've enhanced that with FAST (Fleet Anti-Terrorism Security Team) teams and others so that if they are requested, they can respond more quickly."
Sudanese Foreign Minister Ali Karti on Saturday flatly rejected a US request to send special forces to protect the Khartoum embassy, the official SUNA news agency said, quoting his office.
Hours later, US officials announced Washington would evacuate all non-essential staff and family members from Sudan and Tunisia, and warned US citizens against travel to the two countries.
The US embassy in Yemen, meanwhile, suspended all consular services for two weeks, the mission said on its website, after four people were killed in violent anti-American protests in Sanaa.
'Killings not warranted'
Across the Muslim world protesters have since vented their fury at the "Innocence of Muslims" -- an amateur film produced in the United States -- by targeting symbols of US influence ranging from embassies and schools to fast food outlets.
Although the US government itself has condemned the film, protests erupted again on Sunday, with hundreds of students pouring into the streets of Kabul shouting anti-American slogans, as the Bangladesh government condemned the film as "reprehensible" and New Delhi called it "offensive."
Belgian police said they detained 230 people in the northern city of Antwerp after clashes at a demonstration against the film.
Protests were also staged in Britain, Niger, Pakistan, Turkey and France, whose interior ministry said it would block any further anti-American demonstrations over the film.
With Muslim anger boiling, AQAP on Saturday called for more violence against US diplomatic missions in the Middle East and Africa, and urged attacks on American interests in the West, the SITE Intelligence Group said.
AQAP, Al-Qaeda's Yemeni offshoot, did not claim direct responsibility for the deadly attack in Benghazi.
But it said the killing of Libi in a June drone strike in Pakistan "increased the enthusiasm and determination of the sons of (Libyan independence hero) Omar al-Mukhtar to take revenge upon those who attack our Prophet," according to SITE.
In Afghanistan, heavily armed Taliban fighters on Friday stormed a strongly fortified air base in Helmand province where Britain's Prince Harry is deployed, killing two US Marines in an assault the militia said was to avenge the anti-Islam film.
A NATO spokesman on Sunday revealed six US fighter jets and three refuelling stations were destroyed and six aircraft hangars damaged in the attack, the scale of which he said was unprecedented.
A total of 17 people have died in violence linked to the film, including the four Americans killed in Benghazi, 11 protesters who died as police battled to defend US missions from mobs in Egypt, Lebanon, Sudan, Tunisia and Yemen, and the two US soldiers in Afghanistan.