Original story posted at 10:53 a.m.
A man armed with an assault rifle shot his way through a Terminal 3 security gate at Los Angeles International Airport Friday morning, killing a security agent and wounding at least one more before being shot by police and taken into custody.
The gunfire erupted around 9:30 a.m. inside the terminal that houses airlines such as Allegiant Air, Frontier, Spirit, Virgin America and JetBlue.
Patrick Gannon, chief of the Airport Police Department, said the suspect -- later identified by the FBI as 23-year-old Paul Anthony Ciancia -- walked into the terminal, pulled an assault rifle out of a bag and started shooting. The weapon was believed to be an AR-15 assault rifle.
"He proceeded up into the screening area where TSA screeners are and continued shooting," Gannon said, adding that the gunman "went past the screeners and back into the terminal itself."
Gannon said police pursued the gunman, who was shot and taken into custody inside the terminal. The gunman's condition was not immediately known.
Interim Los Angeles Fire Chief Jim Featherstone said paramedics treated seven people at the airport, and six were taken to area hospitals. One person apparently declined to be transported, fire officials said.
Mayor Eric Garcetti said at least three people were shot. FBI officials some of the people injured were apparently hurt while trying to escape the gunfire.
The Transportation Security Administration issued a statement saying "multiple" TSA officers were injured, "one fatally." According to Craig Harvey of the coroner's office, the victim was a roughly 40-year-old man, and he died around 11 a.m. at Harbor-UCLA Medical Center.
He was the first TSA agent killed in the line of duty.
The hospital's Dr. David Plurad said the man had no signs of life when he arrived at the hospital. He was suffering from "multiple" gunshot wounds to the chest and abdomen. Plurad said at least one bullet apparently fragmented, causing more extensive internal injuries.
J. David Cox, president of the American Federation of Government Employees, the union that represents TSA officers, said the victim was a "behavior determination officer" who had just transferred to LAX from Montana.
Harvey said the coroner's office had not been notified about any other fatalities stemming from the shooting.
A second patient was treated for minor shoulder injuries at Harbor-UCLA Medical Center. Officials at Ronald Reagan UCLA Medical Center said they treated three male patients, one in critical condition -- possibly Ciancia -- and one in fair condition. The third patient was also brought to the hospital in fair condition and was released by mid-afternoon, according to the hospital.
Another patient was believed to have been taken to Marina del Rey Hospital.
Some media outlets reported that Ciancia was carrying a hand-written message saying he wanted to kill TSA agents, although federal and local authorities would not confirm the reports. Media reports from his hometown of Pennsville, N.J., indicated that the suspect's father had contacted police Thursday saying he was concerned his son was planning to commit suicide.
Some initial reports indicated that a second suspect had been arrested, but Gannon said, "This was a lone shooter," and the gunman "was the only person that was armed in this incident."
Mayor Eric Garcetti said the shooter had a large supply of ammunition and could have done far more damage had he not been arrested.
"There were more than a hundred more rounds that could have literally killed everybody in that terminal today," he said. "If it were not for their (police officers') actions, there could have been a lot more damage."
David Bowdich, FBI special agent in charge for Los Angeles, said that in addition to the TSA agent who was killed, at least one other agent had been wounded by gunfire.
"There are additional injuries, some of which seem to be potential evasion injuries where they may have injured themselves trying to get away," he said.
Bowdich said Terminal 3 was expected to remain closed for "a while" while investigators continued combing through the building for evidence.
He asked that anyone who might have information about the shooting or the investigation to call a tipline at (888) 226-8443.
The FBI issued a statement saying it had not made any determination about whether the shooting had any connection to terrorism.
"It would be premature to comment on a motivation at this time and joint investigators have neither ruled out terrorism, nor ruled it in," according to the FBI.
President Barack Obama told reporters in Washington, D.C., that he had been briefed on the shooting and was "concerned about it."
The outbreak of gunfire sparked chaos inside the terminal, as passengers hit the floor to avoid the gunfire and scrambled to evacuate.
A witness told KNX radio that people began scrambling to evacuate the terminal when the shots rang out. She said some people were directed out through emergency exits onto the tarmac until they were picked up by buses and taken to another terminal.
Airline passenger Dana Starfield told KCAL9 she and other passengers hid in a closet at the terminal after the shots rang out.
"We were all just texting our families and where we were," she told the station. "... I just let them know where I was and that I was OK."
Another witness told a Wisconsin radio station that the gunman walked past him and asked him if he was with the TSA. The witness said he shook his head no, and the gunman moved on.
Century Boulevard was closed off, blocking all traffic into LAX, and motorists were advised to avoid the area. Traffic was at a standstill on streets heading toward the airport. Freeway exits near the airport, on Interstates 105 and 405, were also closed.
A ground stop was issued for the airport, meaning planes around the country bound for LAX were being held on the ground. Some planes already in the air were landing at LAX, and planes at other LAX terminals were being allowed to depart, according to the airport.
Gina Marie Lindsey, head of Los Angeles World Airports, the city agency that operates the airport, said a total of 746 flights were affected by the near shut-down of the airport, with 46 inbound flights diverted to other airports.
With Terminal 3 expected to remain closed, flights that normally operate out of those gates would likely be moved to other terminals. She urged passengers to keep in contact with their airlines for flight information.
Hundreds of passengers were evacuated out of terminals as police searched the airport throughout the day. Crowds of passengers could be seen packed into other terminals, standing on sidewalks or lining streets around the airport.
The shooting was the first of its type at LAX since 2002, when an Egyptian-born Irvine resident opened fire at the El Al ticket counter on the Fourth of July.
El Al employee Victoria Hen and Yaakov Aminov, who was at LAX to see a friend off, were killed and several other people were injured before the gunman -- Hesham Mohamed Hadayet -- was shot dead by an El Al security officer.
The airport was also the source of security concerns last month when a pair of dry ice bombs exploded in areas not accessible to the general public. Two employees of an airport contractor were arrested and charged in connection with those explosions, which did not cause any injuries.