The gunman ignored the travelers shuffling in and out of Los Angeles International Airport. He ignored the airline employees printing tickets and checking bags.
Instead, he scanned Terminal 3 for an airport security official, authorities said.
Only then did he open fire.
Gerardo Hernandez, 39, was shot at point-blank range and crumpled to the floor, authorities said. The gunman rode up an escalator, turned around and noticed the bleeding man squirming.
He went back and fired again, authorities said, killing Hernandez.
Authorities filed a murder charge Saturday against the man they allege opened fire, Paul Anthony Ciancia, 23, and offered chilling new details that suggested the rampage was explicitly aimed at Transportation Security Administration agents.
The gunman was carrying a signed, handwritten note in his duffel bag that said he wanted to "instill fear into their traitorous minds," said David Bowdich, special agent in charge of the Counterterrorism Division at the FBI's Los Angeles office.
"His intent was very clear in his note," Bowdich told reporters Saturday. "In that note he indicated his anger and his malice toward the TSA officers."
A law enforcement official told The Times that the screed resembled a "suicide note." The gunman said he didn't want to hurt anyone "innocent" — only TSA agents. The note also mentioned "NWO," a possible reference to the New World Order, a conspiracy theory that holds that forces are trying to create a totalitarian one-world government.
The shooter was apparently dropped off at LAX just after 9 a.m. Friday, authorities said, though they gave no details about the driver. The triggerman wore dark clothes and a bulletproof vest and had not purchased a ticket. He carried a Smith & Wesson .223-caliber M&P-15; assault rifle, five loaded magazines and a trove of ammunition, Bowdich said.
After shooting Hernandez, authorities and witnesses said, the gunman calmly fired his way through the screening area, all the while cursing TSA agents. He asked terrified bystanders: "Are you TSA?" If they answered no, he moved on.
In a 10-minute rampage that was captured on video, the shooter wounded two more TSA agents and injured at least one bystander, authorities said. Some travelers ducked behind planters and advertising kiosks to avoid gunfire; others fled to taxiing planes. Airport police, who were "60 seconds behind the suspect," according to airport Police Chief Patrick Gannon, shot the gunman in the leg and head near a food court.
The accused shooter remains "unresponsive" at a local hospital, said authorities, who have been unable to interview him. In addition to murder, federal prosecutors charged him with committing violence at an international airport. If convicted, the suspect could face life in prison or the death penalty.
The rampage temporarily halted traffic at the nation's third-busiest airport, stranding thousands of passengers. Terminal 3, which houses Virgin America, JetBlue and other airlines, reopened Saturday afternoon.
Hernandez was the first TSA agent slain in the line of duty.
On Saturday, Hernandez's widow briefly addressed reporters, praising her husband as an ever-smiling father of two who came to L.A. from El Salvador at age 15 and joined the TSA three years ago. A neighbor said he routinely woke up at 3 a.m. to get to LAX on time.
"He was always excited to go to work," said Ana Hernandez, who struggled to remain composed. "I am truly devastated."
John S. Pistole, who oversees the TSA, joined Hernandez in front of the family's Porter Ranch home. He said the unarmed TSA agents — often derided in politics and pop culture as an airport nuisance — were, in many respects, "the first line of defense" against violence.
He said the agency plans to reassess its policies, though he acknowledged that "we can't guard against all threats and all risks." J. David Cox, president of the union that represents 45,000 TSA employees, said airports should station armed security guards at each checkpoint, and that it should be a federal crime to assault a TSA officer.
Investigators said they were combing Ciancia's background for a possible motive. The unemployed motorcycle mechanic grew up in the Philadelphia suburb of Pennsville Township, N.J., where his father runs an auto body shop.
The success of Salem County Collision afforded the family beach vacations, private school tuition for their children and renovations to their stately home, said longtime family friend Alan Levitsky. Some of the work on the house — ramps and an elevator — was done to accommodate a wheelchair for Ciancia's mother, who suffered from multiple sclerosis, Levitsky said. She died in 2009.
"It was tough on the kids," he said.
In recent years, Ciancia's father had been training his son to take over the body shop, Levitsky said. In 2011, Ciancia graduated from the Motorcycle Mechanics Institute in Orlando, where he learned to fix Harley-Davidsons.
"He was a sweet kid. A good, quiet boy. Nothing abnormal," Levitsky said, adding that he showed no signs of the political obsessions on display in the note the FBI described. "I don't know where any of that came from. The dad is not political at all."
Ciancia moved to Los Angeles about 18 months ago, said Allen J. Cummings, the Pennsville police chief, who is friends with Ciancia's father. They had no indication Ciancia was struggling, Cummings said, or that he may have harbored anti-government sentiments.
"We don't really know what happened out West," Cummings said. "We don't know where he got his ideas or where that came from."
By Friday, Cummings said, Ciancia had sent text messages to his brother and sister, indicating that he wanted to harm himself. His sister alerted the LAPD, Cummings said, but officers visited his apartment and said they found nothing amiss.
Later that day, with news crews swarming LAX, Ciancia's father called Cummings. "I'm watching TV," he told the chief, "and I think this is my son at the airport."
Times staff writers Robert Faturechi, Brian Bennett, Rick Rojas, Jason Wells, Alicia Banks, Dan Weikel, Laura J. Nelson, Abby Sewell and Joseph Tanfani contributed to this article. Tanfani reported from New Jersey and Bennett from Washington, D.C.