The FBI raided a Tennessee apartment as investigators tried to determine whether at least two acquaintances of Chattanooga shooter Mohammad Abdulazeez knew of his plans in the months leading up to the deadly rampage.
Agents converged on the Mountain Creek Apartments complex in Red Bank, north of Chattanooga, on Monday afternoon. Ed Reinhold, the FBI special agent in charge of the investigation, said investigators have been "going all over this city talking to different friends and associates of our shooter."
Abdulazeez, 24, opened fire at a military recruiting station and a Navy and Marine reserve center Thursday, killing four Marines and a sailor and wounding a local cop.
A family representative told NBC News that he was battling depression, had expressed some anti-American feelings and was on a three-day downward spiral before the attack.