misrata/benghazi libya man seize u.s. force libya accuse involvement attack kill u.s. ambassador benghazi 2012 syrian link suspect ringleader libyan military officials say tuesday u.s. special force capture mustafa al-imam past days transport unite state u.s. officials say monday without give detail speak condition anonymity eastern-based military officials tell reuters imam believe syrian national age 35 40. capture near misrata country third-largest city locate 190 km east capital tripoli say mohammed al-ghasri spokesman defense ministry u.n.-backed government tripoli catch near city misrata movements monitor ghasri tell reuters first official statement tripoli-based government ask whether libyan authorities present u.s. operation say yes ... coordination security agencies inside misrata city decline elaborate man originally eastern libya spend time misrata root also move around ghasri add live misrata imam previously live benghazi district laithi frequent al-awza mosque suspect ringleader ahmed abu khatallah snatch u.s. force 2014 eastern military officials say u.s. prosecutors open case abu khatallah month imam charge kill person course attack federal facility provide material support terrorists result death u.s. justice department say appear federal judge washington arrive unite state laithi islamist stronghold saw heavy fight battle control benghazi begin 2014. july eastern-based military commander khalifa haftar announce victory campaign pit libyan national army lna islamists opponents libya rival governments one capital another east ally haftar eastern news agency back lna publish say picture imam stand front benghazi barrack arm group take haftar force benghazi attack kill ambassador christopher stevens three americans topic numerous congressional hear republican lawmakers critical way then-secretary state hillary clinton handle attack libya mire conflict since 2011 overthrow muammar gaddafi islamist militants gain grind fight rival factions create security void man seize benghazi attack syrian link suspect ringleader -libyan officials