(CNN) -- The deadly attack on the U.S. Consulate in Benghazi underscores the gaping power vacuum across Libya since the toppling of Moammar Gadhafi's regime last year. Fighting groups that battled Gadhafi have stepped in to maintain law and order after the fall of the regime, an expert on post-Gadhafi Libya told CNN. Most of the groups are simply neighborhood watch entities. But some include hard-line Muslim Salafis and have "a very Islamist orientation," said Frederic Wehrey, a senior associate in the Middle East Program at the Carnegie Endowment for International Peace. The group accused of being behind the consulate assault, the Imprisoned Omar Abdul Rahman Brigades, is said to be pro-al Qaeda.
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Sufi shrines and Western entities have been targeted in Libya
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Militia groups are trying to maintain law and order
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The government uses militants "as hired guns," emboldening them, an analyst says
Wehrey, in speaking to CNN, cited two of his recent essays about security in @placeholder.