Paul Ciancia, 23, is unresponsive and under 24-hour guard at Ronald Reagan UCLA Medical Center in Westwood.
An official briefed on the case says Ciancia was dropped off at LAX like a passenger by a roommate who didn't know what was about to happen. Federal prosecutors say Ciancia walked into the airport, pulled out an assault rifle at Terminal 3 and fired repeatedly at TSA officer Gerardo Hernandez, killing him.
Prosecutors say he then fired at two other uniformed TSA officers and a Calabasas High School teacher who was preparing to board a flight. All three were wounded before airport police shot Ciancia four times and arrested him. Authorities say moments after Ciancia was taken into custody, he hold them he acted alone.
It's unclear why the suspect targeted TSA officers, but Rep. Michael McCaul, R-Texas, chairman of the House Homeland Security Committee, says he has seen the note Ciancia left behind and says the 23-year-old made it very clear who he was targeting.
"The suicide note that I read talks a lot about killing TSA agents, and he said, 'If I kill just one, my mission is accomplished,' and unfortunately he did do that the other day," said McCaul.
Eyewitness News has learned that Ciancia was a student in the motorcycle technology program at Universal Technical Institute in Orlando, Fla. He graduated in 2011.
The FBI says it's still looking into Ciancia's past to try to figure out what his motive was and why TSA officers were targeted. Investigators have also talked with authorities at the trade school in Florida, but so far no solid clues.
Hernandez is the first TSA officer killed in the line of duty in the 12-year history of the agency. The 39-year-old leaves behind a wife, young son and daughter.
Sunday afternoon, authorities released the names of the two TSA officers injured in the shooting. The victims were identified as James Speer, 54, and Tony Grigsby, 36. Both officers have been released from the hospital and are now at home recovering from their injuries. Speer joined the TSA in May 2008 and Grigsby joined the agency in December 2004.
One of the shooting victims, teacher Brian Ludmer, 29, remains in the hospital. He is in fair condition and faces another surgery on Monday after being shot in the leg.
"He saw the gunman out of the corner of his eye, and he felt his leg below the knee turn into like jelly," Las Virgenes Unified School District Superintendent Dan Stepenosky said.
As LAX returns to normal, reminders of Friday's violence are easy to spot in Terminal 3. Extra officers are on patrol and luggage remains piled up waiting to be claimed.
"Our baggage didn't come. The plane was locked. We couldn't get our baggage until last night," said Bobby Eisman, a passenger from Ft. Lauderdale.
Anyone with information, photos or videos of the shooting at LAX is asked to call the FBI Los Angeles tip line at (888) 226-8443 or visit laxshootingtips.fbi.gov .