Dzhokhar Tsarnaev, a surviving suspect in the Boston Marathon bombings, was reportedly captured on video placing a bomb; authorities are investigating the Tsarnaev brothers’ possible links to Islamic extremist groups. US citizen Abdella Ahmad Tounisi was arrested at O’Hare airport as he attempted to fly to the Middle East to join the al Qaeda-linked Al Nusrah Front. Tounisi, from Aurora, Ill., is an associate of Adel Daoud, who tried to detonate a bomb in Chicago in September 2012.
