LAX shooting: Latest On Suspect, Victims

After a weekend of intense investigation, authorities are piecing together more details about Friday's fatal shooting at Los Angeles International Airport, including the suspect's behavior earlier in the week and a warning from his family that may have come minutes too late.

Officers sent to check on Paul Ciancia's welfare arrived at his apartment less than an hour after the shooting started, police said Monday, CNN's Kyung Lah reports.

About 9:20 a.m. Friday, Ciancia walked up to a Transportation Security Administration checkpoint in Terminal 3. He pulled a .223-caliber assault rifle from a bag and shot TSA officer Gerardo Hernandez "at point-blank range," according to a court document filed by an FBI agent.

Ciancia then went up an escalator but returned to shoot Hernandez again, apparently after seeing him move.

He continued walking and shooting. Witnesses said he went from person to person, asking, "Are you TSA?"

Hernandez, 39, was the first TSA officer to die in the line of duty since the agency was created in 2001.

"He took pride in his duty for the American public and for the TSA mission," said his wife, Ana Hernandez.

The couple, who married in 1998, have two children.

Two other TSA officers - James Speer, 54, and Tony Grigsby, 36 - were wounded but were released from the hospital.

Grigsby, who was shot in the foot, told reporters Monday he was injured while helping an elderly man move to a safe area.

"I turned around and there was a gunman," he said. "Shot me twice."

A traveler who was shot in the leg, 29-year-old Brian Ludmer of Lake Forest, Illinois, was in fair condition Sunday.