Hours before the Tennessee shooting that killed five U.S. servicemen, the suspected gunman texted a close friend a link to an Islamic verse that included the line: "Whosoever shows enmity to a friend of Mine, then I have declared war against him."
The gunman's family said in a statement late on Saturday he had suffered from depression, and that they had experienced shock and horror over the violence.
The suspect's friend said he thought nothing of the text message at the time, but now wonders if it was a clue to Thursday's rampage in Chattanooga, which has re-ignited concerns about the radicalization of young Muslim men.