Gunman told police he acted alone in LAX shooting; Ciancia dropped off at the airport by a friend.

Byline: Tami Abdollah

LOS ANGELES -- The 23-year-old charged as the gunman in the deadly shooting at Los Angeles International Airport told authorities at the scene that he acted alone and had been dropped off by a friend, a law enforcement official who has been briefed on the investigation told The Associated Press on Sunday.

Authorities do not believe the friend knew that Paul Ciancia, the man charged in the attack, planned to open fire inside LAX's Terminal 3 just moments later, killing one Transportation Security Administration officer and wounding three other people, including two more TSA workers, said the official, who is not authorized to speak publicly about the investigation and requested anonymity.

Ciancia was dropped off in a black Hyundai and was not a ticketed passenger. He was able to respond to investigators' questions at the scene Friday, the official told the AP exclusively.

Ciancia, an unemployed motorcycle mechanic who grew up in the small, blue-collar town of Pennsville, N.J., was shot four times and was under 24-hour armed guard at the hospital, the official said. Ciancia was sedated for medical reasons, the official said, adding that one gunshot to the mouth blew a molar out of the suspect's jaw

Federal prosecutors charged Ciancia on Saturday with murder of a federal officer and committing violence at an international airport. The charges could qualify him for the death penalty.

In court documents and interviews, authorities spelled out a chilling chain of events, saying Ciancia walked into the airport, pulled a .223-caliber assault rifle from his duffel bag and fired repeatedly at point-blank range at 39-year-old TSA officer Gerardo I. Hernandez, killing him.

He then fired on at least two other uniformed TSA employees and an airline passenger, who all were wounded, before airport police shot him as panicked passengers cowered in stores and restaurants, authorities said.

It wasn't clear why Ciancia targeted TSA officers, but what he left behind made it clear he intended to kill any of them who crossed his path, FBI Agent in Charge David L. Bowdich said.

The shooter's duffel bag contained a handwritten letter signed by Ciancia stating he'd ''made the conscious decision to try to kill'' multiple TSA employees and that he wanted to ''instill fear in their traitorous minds,'' Bowdich said.

The letter also talked about ''how easy it is to get a gun into the airport,'' the law enforcement official said.

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