Islamist radicals in Libya have threatened to take revenge on Westerners for the "kidnapping" by US forces of a former associate of Osama bin Laden, who was seized from in Tripoli on Saturday.
A growing wave of anger has been directed at the Libyan government from all sides over the capture by US Delta Force marines of Abu Anas al-Libi, who was accused of helping to plan attacks on the American embassies in Nairobi, Kenya, and Dar es-Salaam, Tanzania, in 1998, which killed 224 people.
Some say the fact that the arrest was carried out by Americans showed that the Libyan government is too weak to enforce law and order for itself. But many Islamists accuse the Libyan government of secretly participating in the raid and say they will attack Western interests and even kidnap foreigners in revenge.
One Facebook page, "Benghazi is Protected by its People", urged followers to seal off roads to Tripoli and kidnap Americans and other foreigners to use as bargaining chips for exchange. "We call for targeting any aircraft or vessel related to the Americans and their allies," it added. "The basic principle is fighting support for the infidels."
Another, by "The Revolutionaries of Benghazi, Al-Bayda and Derna", said: "We condemn this act, and pledge before God to fight those who betrayed their country and involved themselves in this plot." Benghazi is Libya's second city, and the starting point of the revolution which overthrew Col Muammar Gaddafi.
Al-Bayda and Derna are well known as bases for militant Islam. The Libyan government issued a statement on Sunday denying knowledge of the raid and demanding clarification from the US for what it also called a "kidnapping".
It has summoned Deborah Jones, the US ambassador, seeking answers. Al-Libi's family said that some of the men who bundled him into an SUV outside his house were speaking Arabic with Libyan accents. They insist al-Libi can prove his innocence.