Broward County Sheriff's Office confirmed the suspect was in custody
Five people were killed during a shooting in Fort Lauderdale airport.
A law enforcement official from Broward County Sheriff's Office confirmed tjhat a further eight people had been transported to hospital with injuries.
The city's mayor said that a lone gunman was responsible for the attack, and emergency services were called to the scene just before 1pm local time (6pm Irish time). The suspect has been taken into custody unharmed and without incident.
Sheriff Scott J. Israel of Broward County addressed members of the press on the situation, denying reports of a second shooter and stating it was "too early to say" if there were any links to terrorism.
Sheriff Israel added: "We have the shooter in custody, he's unarmed - no law enforcement officers fired any shots. The subject is being interviewed by a team of FBI agents and Broward County Sheriff's Office homicide detectives."
US Senator Bill Nelson said the arrested suspect was carrying military ID with the name Esteban Santiago.
On Facebook, Broward County commissioner Chip LaMarca wrote: "The shooter was a passenger on a Canadian flight with a checked gun.
"He claimed his bag and took the gun from baggage and went into the bathroom to load it. Came out shooting people in baggage claim."
Fort Lauderdale-Hollywood International Airport was closed indefinitely in the wake of the attack, with no flights arriving or departing.
Other airports in the state say their services are running as normal but with an increased police presence, while the Port of Miami has introduced enhanced security measures "out of an abundance of caution".
Aerial footage from the scene showed hundreds of people standing on the tarmac as ambulances drove by, with one bleeding victim being treated by medics outside the terminal building.
Images from social media show passengers spilling out on to the tarmac after being evacuated from Terminal 2.
Former White House Secretary Ari Fleischer, who was in the airport at the time of the incident, said that "everyone was running" after shots were fired.
Florida Governor Rick Scott is travelling to the airport, where he will be briefed by law enforcement.
In a statement, Fort Lauderdale Mayor John P. Seller said: "We have our units on site and around the perimeter to provide assistance and support, and we remain ready, willing, and able to provide additional assistance, support and resources.
"Our community extends its thoughts, prayers, and support to the victims and their families."