Police officers enter the Armed Forces Career Centre through a bullet-riddled door after a gunman opened fire on the building on Thursday in Chattanooga. (AP photo)
The US Federal Bureau of Investigation on Thursday identified the gunman in two shootings at military centers in Tennessee that left four Marines dead as 24-year-old Mohammod Youssuf Abdulazeez.
"While it would be premature to speculate on the motives of the shooter at this time, we will conduct a thorough investigation of this tragedy," the FBI said in a statement, adding that three people were injured in the rampage.