The suspect's friend said he thought **thing of the text message at the time, but **w wonders if it was a clue to Thursday's rampage in Chatta**oga, which has re-ignited concerns about the radicalization of young Muslim men. The suspect, Mohammod Youssuf Abdulazeez, a Kuwaiti-born naturalized U.S. citizen, was killed in a gunfight with police. The Federal Bureau of Investigation (FBI) is investigating the attack as an act of terrorism, but said it was premature to speculate on the gunman's motive.