Libyan Prime Minister Mustafa Abu Shagur
Libyan Prime Minister Mustafa Abu ShagurAFP/Mahmud Turkia

A “big advance” has been made in the probe into the attack on the U.S. consulate in the Libyan city Benghazi, Prime Minister Mustafa Abu Shagur told AFP in an exclusive interview Thursday.

“We have made a big advance,” Abu Shagur said, in his first interview since his election as premier on Wednesday night.

“We have some names and some photographs. Arrests have been made and more are under way as we speak,” he added.

Abu Shagur did not elaborate on how many suspects were in custody or what groups, if any, they were connected to.

"We don't want to categorize these people until we know all the facts," he said.

Deputy Interior Minister Wanis al-Sharif was similarly reticent about going into details when he spoke to AFP earlier Thursday.

“The interior and justice ministries have begun their investigations and evidence gathering and some people have been arrested,” he said, declining to give any details of the number of people in custody or their backgrounds "so as not to hamper the smooth running of the investigation."

Initial reports said Ambassador Chris Stevens and three other Americans were killed by a mob outside the consulate in Benghazi on Tuesday as they tried to flee an angry protest against a U.S.-produced movie deemed offensive to Islam.

But it is now believed Stevens died from smoke inhalation after becoming trapped in the compound when suspected Islamic militants fired on the building with rocket-propelled grenades and set it ablaze.

U.S. officials are investigating the possibility that the assault was a plot by Al-Qaeda affiliates or sympathizers, using the protest against the film as a cover to carry out a coordinated revenge attack on Tuesday's anniversary of the September 11, 2001 attacks in the United States.

Abu Shagur played down the Al-Qaeda line, telling AFP, “We don't have any proof as yet of an Al-Qaeda presence as an organization in Libya," although "some youths have been influenced by the extremist ideology of Al-Qaeda," he said.

Abu Shagur said extremists were a tiny minority in Libya who "do not number more than 100 or 150," whereas most young Islamists in the country were moderates.

The attack on the U.S. consulate was "a cowardly, criminal and terrorist act," he said, adding it was "isolated, not representing a phenomenon in Libyan society and it will not have negative consequences with our allies" who backed last year’s revolution which toppled former leader Muammar Qaddafi.

The United States evacuated most of its diplomatic staff from Libya and flew them to Germany after the attack. All diplomatic missions around the world have also been ordered to review their security.

Anti-American violence spread across the Middle East, with mobs rioting at U.S. missions in Tunisia, Sudan and Morocco over the past two days.