Libya's interim President, Mohammed el-Megarif, suggested on Sunday that al Qaeda was behind the deadly assault on the US consulate in Benghazi, which claimed the life of the US ambassador.
"I won't be surprised to discover that they were the planners of this sinister attack on American consulate, particularly when we think of, or we consider they are choosing the 11th of September as the date for carrying out this operation," el-Megarif told AP Television in Benghazi.
El-Megarif said that the second part of the attack, on a safe house used by consulate workers, shows the assault was planned in advance.
"All this indicates clearly that the attackers are well trained and well prepared and have planned this in advance."
His comments contrast with the American view on Sunday, which suggests that Tuesday's attack was not a premeditated assault tied to the anniversary of September 11th.
The US ambassador to the United Nations said on Sunday that the assault, which also killed three other Americans, was a spontaneous reaction to an anti-Muslim video.
Susan Rice said that evidence gathered by a White House investigation into the attacks so far shows no indications of a premeditated or coordinated strike.
She said the deadly protest in Benghazi appeared to be a copycat of demonstrations that had erupted hours earlier outside the US Embassy in Cairo, spurred by excerpts from a film posted on YouTube mocking the Prophet Muhammad.
El-Megarif said on Sunday that the investigation into the attacks was ongoing and that a number of arrests had been made.
He said the Libyan authorities would cooperate fully with the US government in its investigation.
"The Americans being the target of this attack, I think it's our duty, it's our responsibility to invite them to help us in carrying out the investigation."