National Security

Umar Farouk Abdulmutallab, here in Milan, Mich., was charged in federal court in December with trying to detonate an explosive device on a Dec. 25 flight from Amsterdam to Detroit. U.S. Marshals Service/AP hide caption

The building housing the San'a Institute for the Arabic Language in Yemen's capital, where Umar Farouk Abdulmutallab studied. Peter Kenyon/NPR hide caption

Regent's Park Mosque, also known as London Central Mosque, where Umar Farouk Abdulmutallab worshiped while he was living in London from 2005 to 2008. An ex-member of a radical Islamist group says gatherings at the mosque, and others like it, are used to identify potential recruits. Courtesy of Pucasso via Flickr hide caption

University College London, where Abdulmutallab studied from 2005 to 2008, is one of 12 British universities on an intelligence agency watch list. Courtesy stevecadman via Flickr hide caption