By Jonathan Allen and Jonathan Kaminsky
(Reuters) - The suspect in a deadly shooting at Los Angeles International Airport wrote that he intended to die after killing at least one security officer, the head of a key congressional security committee said on Sunday, as authorities stepped up patrols at the airport and considered changes to aviation security rules.
Paul Anthony Ciancia, 23, also discussed weaknesses in airport security in the "suicide" note before Friday's attack, Michael McCaul, the Republican chair of the House Committee on Homeland Security, told CNN.
"The other thing he wanted to talk about was how easy it is to bring a gun into an airport and do something just like he did," McCaul said of the note.
An officer with the Transportation Security Administration died in the shooting, the first employee from the agency killed in the line of duty since it was created after the September 11, 2001 attacks. Three others were wounded on Friday.
Extra uniformed and plainclothes police were patrolling Los Angeles' international airport, the world's sixth-busiest, as it resumed full operations on Sunday, said Sergeant Belinda Nettles, spokeswoman for the Los Angeles Airport Police.
Passengers were cautioned to expect delays, Nettles said.
The shooting also has brought calls for improved U.S. airport security. The alleged gunman is believed to have deliberately taken advantage of security vulnerabilities and targeted TSA agents with an assault weapon before police shot and wounded him, ending the rampage.
The federal Transportation Safety Administration is exploring changes to security at Los Angeles' international airport and other airports, TSA Administrator John Pistole told reporters on Saturday.
"We have been discussing what the policies and protocols have been to now," Pistole said. "Obviously, this gives us great concern." He did not additional provide details.
McCaul said the note allegedly written by Ciancia "talks a lot about killing TSA agents, and he said, 'If I just kill one, my mission is accomplished.'"
In a criminal complaint filed on Saturday, investigators said they found a handwritten letter signed by Ciancia in his bag that addressed TSA officials, writing that he wanted to "instill fear in your traitorous minds."
It was not immediately clear whether McCaul was referring to the same note mentioned in the complaint.
Investigators have declined to discuss a possible motive for Ciancia's reported grievance with the TSA.
Authorities charge that Ciancia walked into the airport's Terminal 3 on Friday morning, took out an assault rifle from his bag and opened fire, shooting dead Gerardo Hernandez, a 39-year-old TSA officer at a document checkpoint.
Ciancia, authorities charge, then went on to shoot and wound two other TSA employees and a passenger, prompting a panicked evacuation.
The passenger, Brian Ludmer, described in local media reports as a 29-year-old high-school teacher, was awaiting further surgery on his fractured leg at Ronald Reagan UCLA Medical Center, a spokesman for the hospital said on Sunday.
Another victim, who has not been identified, remains in critical condition, the spokesman said.
The U.S. attorney in Los Angeles has charged Ciancia with murdering a federal officer and committing violence at an international airport, crimes that carry a possible death penalty if Ciancia is convicted.
McCaul also said that police visited Ciancia's home after being alerted by worried relatives, but he had already left for the airport.
Ciancia's father, who lives in Pennsville Township, New Jersey, called local police before the shooting after Ciancia, who moved to California 18 months ago and lives in suburban Los Angeles, sent his brother a worrisome text message.
McCaul said police in Pennsville contacted Los Angeles police, who then "visited the suspect's home the morning of the shooting and missed him by literally, probably, 45 minutes."
Andy Neiman, an LAPD spokesman, said on Sunday that before the shooting began, officers went to Ciancia's home and spoke to his roommates. They said they had seen Ciancia that morning before he left the house.
"His roommates had seen him and said he was in good shape and there was no additional follow-up," Neiman said.
(Reporting By Jonathan Allen; Editing by Scott Malone, David Brunnstrom, Sharon Bernstein and Paul Simao)