The 24-year-old named by the FBI as the killer of four U.S. Marines today in Chattanooga, Tenn. today so far does not appear to have been on law enforcement’s radar, two U.S. officials told ABC News. “They’ve run an initial check on him. Right now, there is nothing popping early in the system on him, but that could change,” a senior U.S. official briefed on the incident said. “They are still checking multiple other databases on him.” Authorities are investigating the life of Abdulazeez in an attempt to determine what may have prompted him to carry out the deadly attack.