The father of the young man suspected of carrying out a fatal shooting at Los Angeles International Airport called his local police chief around the time of the shooting to report that his son had sent a suicidal text message to a sibling and he needed to find him, a New Jersey police chief said.
Paul Ciancia, father of the 23-year-old suspect of the same name, called Pennsville Police Chief Allen Cummings in the early afternoon yesterday to tell him one of his children had received a text message from the younger Ciancia "in reference to him taking his own life", the chief told The Associated Press.
Across the country and around the same time yesterday, authorities say, his son was shooting his way past a security checkpoint at the airport with a semi-automatic rifle, killing a security officer and wounding other people. Ciancia was injured in a shootout and taken into custody, police said.
Los Angeles Airport Police Chief Patrick Gannon said the gunman entered Terminal 3, pulled an assault rifle from a bag and began shooting, then fired more shots at a screening checkpoint, where a security agent was checking passenger documents, before entering the secure area of the terminal.
Officers exchanged fire with the gunman and apprehended him. Police believe he was the only shooter, Mr Gannon said.
''As you can imagine, a large amount of chaos took place in this entire incident,'' he said.
Panicked travellers dropped to the ground. Those who had made it past security fled on to the tarmac or sought cover inside restaurants and lounges.
A motive was not clear, but Ciancia was wearing fatigues and carrying a bag containing a handwritten note that said he "wanted to kill TSA and pigs", according to a law enforcement official.
Mr Cummings said his police department in Pennsville, New Jersey, had never had dealings with the younger Ciancia, and neighbours in the working-class city of about 14,000 did not have a clue anything might have been wrong.
"He was never weird toward me. He never gave me any weird vibes," said 17-year-old neighbour Josh Pagan, adding that in the 10 years he has lived across the street from the Ciancia family, "they've been nothing but nice to us".
The suspect graduated in 2008 from Salesianum School, an all-boys Roman Catholic school in Wilmington, the school said.
Outside the father's home in Pennsville, a police cruiser blocked the long driveway. Phone calls were not answered, and efforts to reach siblings were also unsuccessful.
After getting the call from Ciancia's father, Mr Cummings reached out to Los Angeles police, who sent a patrol car to Ciancia's apartment. It was not clear whether the police visited before, during or after the airport shooting.
"Basically, there were two room-mates there," Mr Cummings said. "They said, 'We saw him yesterday and he was fine'."
He told Ciancia's father that because of his son's age, he could not take a missing persons report.