Who could be behind 'sophisticated' bombing at US embassy in Turkey? Barbara Starr & Fran Townsend weigh inUpdated 9:44 AM ET, Fri February 1, 2013 Chat with us in Facebook Messenger. Find out what's happening in the world as it unfolds.JUST WATCHED'Sophisticated' bombing at US embassy?ReplayMore Videos ...MUST WATCH'Sophisticated' bombing at US embassy? 02:35CNN's Barbara Starr & contrib. Fran Townsend on who could be behind a suicide bombing at U.S. Embassy in Ankara, Turkey.