US authorities are investigating the trips Mohammed Youssuf Abdulazeez made to the Middle East before he gunned down four Marines at the Chattanooga Navy facility last Thursday. He spent months in Jordan, possibly Kuwait, where he was apparently born to a Jordanian Palestinian family, and also may have visited Yemen. At some point, he was employed as an engineer at a nuclear plant in Ohio. His employment there was terminated after ten days. Investigators say they are looking for the motive which drove Abdulazeez, 24, a devout Muslim and naturalized American citizen, to spray two unguarded Navy facilities in Chatanooga with bullets from two Kalashnikov automatic rifles and a handgun. Found on his body after he was killed was a “load-bearing vest” stuffed with extra ammunition.