13/09/2012 05:24 BST | Updated 13/09/2012 05:47 BST

Benghazi Embassy Attack: Libyans Demonstrate Against Raid That Killed Chris Stevens (PICTURES)

Libyans took to the streets of Benghazi on Wednesday to protest against the US embassy attacks that led to the death of four US officials, including the American Ambassador, Chris Stevens.

Many of the protesters held placards, some written in English, apologising for the raid on the consulate.

A film ridiculing the Prophet Mohammed sparked the demonstrations, which spread from Egypt to Libya over Tuesday and Wednesday.

However, US officials are currently looking into reports that the attack on the compound, which came on the anniversary of September 11, may have been planned in advance, with reports emerging from Washington suggesting that a militant faction called Ansar al Sharia may have been involved.

"It bears the hallmarks of an organised attack," an American official told Reuters.

The Ambassador, alongside consulate officer Sean Smith and two more Americans colleagues, as yet unnamed, were assassinated by gunmen when the embassy was stormed on Wednesday. According to the Wall Street Journal, up to 10 Libyans were either killed or wounded trying to defend the embassy from the attackers.