Esteban Santiago went to baggage claim Friday afternoon and picked up his one piece of checked luggage.
There were no other bags, just a case with a handgun inside.
Santiago -- who just a few months ago reportedly had a mental evaluation after a bizarre visit to an FBI office in Alaska -- allegedly took the gun out of its case and fired at other passengers, killing five and wounding eight others.
The shooting sent the terminal into chaos, with people running for cover. They started running again when rumors of more gunshots and a possible second shooter spread through busy Fort Lauderdale-Hollywood International Airport. Almost 40 more people would get hurt in the rushed evacuation after the attack. Some suffered sprains and bruises; others had broken bones.
Here's what we know about the deadly shooting and what officials have said about the suspect.
Who is Esteban Santiago?
The man suspected of killing five people Friday at Fort Lauderdale's airport is identified as Esteban Santiago, according to multiple law enforcement officials.
Santiago didn't resist when he was taken into custody, Broward County Sheriff Scott Israel said. According to his booking information, Santiago is being held without bond on a murder charge.
The 26-year-old lives in Alaska, where he was a security guard.
Alaska was also the site of his last military assignment. He was a member of the Alaska Army National Guard from November 2014 until August when he was discharged for unsatisfactory performance, a spokeswoman for the Guard said.
In November, Santiago paid a visit to the FBI office in Anchorage, telling agents he was being directed by a US intelligence agency to fight for ISIS, law enforcement sources told CNN. George Piro, the FBI's special agent in charge, told reporters that Santiago was turned over to local authorities and he voluntarily submitted to a mental health evaluation.
The military said Santiago's nine years of service in the National Guard included one 10-month tour of Iraq, where he was awarded a combat action badge.
How did he get to Fort Lauderdale?
Piro said Santiago flew from Anchorage to Minneapolis to Fort Lauderdale on Delta.
A lieutenant with the Anchorage Airport Police Department said Santiago had one bag -- a handgun case with a pistol inside that he checked.
Authorities do not know why Santiago was in Fort Lauderdale.
What was his motive?
The FBI has not ruled out terrorism, Piro said, but Israel cautioned that it was very early in the investigation and authorities did not know Santiago's motive.
There were reports of a possible altercation involving Santiago on the flight to Fort Lauderdale, but law enforcement sources said investigators haven't discovered any evidence to support those claims.
The airline said it had received no reports of any incidents during the flight.
"Reports from customers and crew onboard the flight in question indicate that there was not a customer altercation during the flight," according to a Delta Spokesperson.
What was it like at the airport?
Sara Graham, whose family had been vacationing in Fort Lauderdale, wrote on Instagram that they were about 100 feet away from the shooter.
Graham said her brother realized there was gunfire and led her and her mother for safety.
"When we first heard the shots we had no idea what was happening until everyone started running towards exits," she wrote. "We hid for about 30 minutes and we're let back inside, under the impression it was all safe."
Then there was a rumor of another shooter and people started running again.
"Once we were outside, we had to run three more times until we were sure that we were safe," she said.
They spent the rest of the afternoon in an aircraft hangar before people were allowed to leave. It is unclear whether the family made it back to Greensboro, North Carolina.
One man told CNN's Anderson Cooper that a laptop in a backpack he had slung over his shoulder stopped a bullet that could have killed him.
"I felt something hit my back," Steve Frappier said, adding that he thought it was luggage falling off the carousel.
It was a bullet, which ricocheted off the laptop. He found it in the side pocket of his bag.
Other witnesses described the aftermath of the shooting as a "war zone" and "mass hysteria."
What are the rules about firearms in airports/checked bags?
Taking a gun on a plane is legal, if the passenger brings the weapon in a case that locks and checks the suitcase containing the gun.
The gun cannot be loaded, though regulations allow travelers who fill out a declaration form to also bring ammunition.
Florida law prohibits guns inside terminals unless they are still in their case, but there is a bill before the state legislature to allow guns in public places like airports.
How was air traffic affected?
The Fort Lauderdale airport was closed for the rest of the day and more than 10,000 travelers had their trips interrupted for hours.
Flight tracking website Flight Aware said 159 arrivals and 149 departures were canceled -- about a third of the scheduled flights.
The airport said services were resuming Saturday morning. It also tweeted late Friday that cargo, private small planes, and corporate jets were to resume operations at midnight.
Roads reopened Saturday morning for passengers and airport employees to reach the airport, according to its Twitter feed. Passengers were advised to check with their airline before traveling.
The airport said earlier it was collecting and processing more than 20,000 bags and personal items left behind during the evacuation in order to return them to their owners.
About 10,000 passengers were taken Friday by bus from the airport to a terminal at Port Everglades in Fort Lauderdale, officials said.
Some people were forced to remain on planes that landed but weren't allowed to reach their gates. One JetBlue passenger said he was stuck for six hours.