Attack may have been Al Qaeda revenge plot, London think tank says – This Just In - CNN.com Blogs A London think tank with strong ties to Libya speculated Wednesday that Stevens was actually the victim of a targeted al Qaeda revenge attack. The assault "came to avenge the death of Abu Yaya al-Libi, al Qaeda's second in command killed a few months ago," the think tank Quilliam said Wednesday. It was "the work of roughly 20 militants, prepared for a military assault," the think tank said, noting that rocket-propelled grenade launchers do not normally appear at peaceful protests, and that there were no other protests against the film elsewhere in Libya. The planned attack came in two waves, one which prompted U.S. officials to leave the consulate for a secure location. The second wave was directed at the place of retreat, Quilliam said, citing unnamed sources on the ground in Benghazi and abroad.