The FBI warned today that anger over the anti-Islamic video setting off protests overseas could spread to the US, reports ABC News. The bulletin, issued with Homeland Security, says extremist groups in the US may use the opportunity to "exploit anger over the film to advance their recruitment efforts." It cites no specific threats but asks religious groups in particular to watch for suspicious activity that suggests plots against "Jewish, Coptic, Islamic, or any other faith-based communities." Libya, meanwhile, has made four arrests in the deadly consulate attack in Benghazi. (More religious violence stories.)