Transportation Security Administration officials Friday night identified the agent killed in a rampage at LAX as Gerardo I. Hernandez, 39.
Officials provided no details about Hernandez. A second TSA agent was also shot at LAX, but he has not been identified.
"No words can explain the horror that we experienced today when a shooter took the life of a member of our family and injured two TSA officers at Los Angeles International Airport," TSA administrator John S. Pistole said in a statement.
"Sadly, today marks the first incident where a TSA officer was killed in the line of duty," he added. "We can take some comfort knowing that the two injured officers are recovering from their wounds."
The gunman was identified by police as Paul Anthony Ciancia, a 23-year-old New Jersey native who lived most recently in Los Angeles.
Authorities declined to discuss the gunman's motivation publicly. But a law enforcement official told The Times that a note was found on the gunman expressing "disappointment in the government" and saying that he had no interest in hurting "innocent people." Ciancia also sent a sibling a text message last week suggesting that he was prepared to die, officials said.
It appears the gunman targeted unarmed Transportation Security Administration agents. Another law enforcement official told The Times that investigators were looking into the possibility that the shooter "wasn't a fan of the TSA."
Authorities said he approached several people cowering in the airport terminal, pointed his gun at them, asked if they "were TSA," and then moved on without pulling the trigger if the answer was no. And a witness told The Times that the gunman cursed the TSA repeatedly as he moved through the terminal.
J. David Cox Sr., president of the union that represents 45,000 TSA flight screeners, called the shooting a "heinous act." The gunman was not a TSA officer and "never had been," according to the union, the American Federation of Government Employees.
The TSA was created in the aftermath of the Sept. 11, 2001, terrorist attacks in an attempt to improve the safety of American transportation. The agency was charged with developing new methods of tightening airport security and preventing hijackings, but is most familiar to the public in the form of its battalion of blue-shirted screeners, who cannot make arrests and do not carry weapons.
A classmate of Ciancia's said Friday that the suspected gunman was a loner and had been bullied at his private high school.
"In four years, I never heard a word out of his mouth," said David Hamilton, who graduated with Ciancia from Salesianum School in Wilmington, Del., in 2008, and is now an editorial assistant at a publishing firm in Philadelphia. "He kept to himself and ate lunch alone a lot. I really don't remember any one person who was close to him."
In all, seven people were injured. Six were taken to area hospitals. It remained unclear if the gunman and the TSA officer who was killed were included in that total. All of those injured were adults, hospital officials said. Some were not shot but suffered what authorities called "evasion injuries" — injuries sustained as they attempted to run.
Shortly after 9 a.m., the man entered the third of LAX's nine terminals through the main door, pulled an AR-15 assault rifle out of a bag and "began to open fire," said Los Angeles World Airports Police Chief Patrick Gannon.
The man walked up one flights of stairs, to the entrance of the security checkpoint; it is there, officials said, where at least three TSA officers were shot. He then entered the airport itself, walking with determination past a candy shop, a newsstand and a bookstore. An airport police officer and sergeant engaged the gunman in a brief gunfight near a food court.
"They hit him multiple times before he went down," said one law enforcement source. A witness said the gunman was wearing a bulletproof vest.
As the gunfire echoed through the terminal, panic erupted and harrowing screams ricocheted down the corridors.
Travelers and employees crawled on the floor and ducked behind planters and advertising kiosks. Passengers tripped over each other and abandoned baggage as they barreled backward through the security check.
Jonathan Paul, 36, of Santa Monica, looked up from a newsstand and saw a wave of terrified people racing toward the main entrance. He said some were shouting: "Go! Go! Go!" Some travelers were halfway through security when the shooting erupted, and raced for the doors with their shoes and belts in hand.
Others, guided by no one and unsure where to go, pushed open emergency exit doors and fled the terminal. Some raced across tarmacs — one woman ran out of her shoes — and some attempted to seek shelter on planes that were still taxiing outside.
Brian Adamick, 43, who was preparing to board a Spirit Airlines flight for Chicago, for his brother's wedding, was among those who escaped the terminal by running onto the tarmac. Before long, buses arrived to evacuate passengers. A wounded TSA officer with a bloody ankle boarded one of them.
"I got shot," the officer told Adamick. "I'm fine."
Stephanie Rosemeyer, 26, was awaiting a flight to Chicago when she saw people running toward the exits. She stood up to look for the source of the commotion, and found herself looking directly into the gunman's eyes. She took a step, and said she heard the gunman curse the TSA. She was among those who raced onto the tarmac and was evacuated by bus.
"There was no one directing anything," she said.
Vernon Cardenas, 45, was one of the last people still inside Terminal 3, and was trying to determine whether he'd be safer running or staying when he found himself face to face with the gunman. The gunman, dressed in dark clothing and no longer carrying a bag, had his weapon pointed to the ground and stared directly into Cardenas' face.
"He wasn't moving like he was being chased," said Cardenas, the executive chef at State Social House restaurant in West Hollywood who was preparing to fly on Virgin America to Philadelphia to conduct auditions for the television show "MasterChef."
Rather, Cardenas said, the gunman was moving slowly and methodically; Cardenas said he thought instantly of the grainy surveillance footage of the teen shooters moving through Columbine High School in 1999 — "roaming around with nowhere to go."
Cardenas ducked outside, through an emergency exit, and remained there until a law enforcement official game him a thumbs up through the window, indicating that it was safe to come back inside.
Outside the airport, a surreal scene unfolded as travelers hurried with rolling bags and strollers past a sea of ambulances and a phalanx of heavily armed law enforcement officials.