Esteban Santiago, 26, who was taken into custody immediately following the shooting and questioned at length, was expected to face federal charges in the shooting rampage, said George Piro, special agent in charge of the Federal Bureau of Investigation's office in Miami.
Piro said investigators had not ruled out terrorism as a possible motive in the rampage and were reviewing the suspect's recent travel.
Santiago, who had served in the U.S. military, had arrived in Ft. Lauderdale shortly before 1 p.m. local time (1800 GMT) on a connecting flight from Alaska, authorities said, when he retrieved a 9mm semi-automatic handgun from his checked luggage and began firing indiscriminately.
Broward County Commissioner Chip LaMarca said on Twitter that the gunman went into a restroom to load his weapon and came out firing. Witnesses told MSNBC television he only stopped after running out of ammunition, at which point he surrendered to police.
Cellphone video posted on social media showed travelers kneeling and treating victims on the floor next to a carousel.Read more at Reuters