LOS ANGELES — In the moments before reports of gunshots created a panic at the Los Angeles airport, police with weapons drawn had confronted a masked man outside a terminal who was carrying a plastic sword and dressed like Zorro.
Authorities have now determined that there were no gunshots. The only people at the airport with guns Sunday night were officers, but false reports of an active shooter triggered a ripple of chaos that sent frantic travelers racing into the streets and onto the tarmac.
As police tried Monday to sort out the disruption, experts said the incident — the second of its kind at a major U.S. airport in two weeks — highlights one of the challenges faced by airports at a time of terrorism and frequent unsubstantiated reports.
“You can’t always avoid them, and when they occur you need to respond as if it’s a legitimate attack every single time,” said Anthony Roman, who runs a security consulting firm in Lynbrook, N.Y. “There are false alarms. There are pranksters who pull fire alarms, and we evacuate right away because we’re all terrified of fire.”
Investigators were focusing on what prompted the first of several 911 calls from multiple terminals, airport police officer Rob Pedregon said. The initial call came from Terminal 8 around 8:45 p.m. — about five minutes after officers detained the man dressed as Zorro.
As a further precaution, flight operations were stopped from 9 to 9:30 p.m. on the airport’s two southern runways because passengers, who self-evacuated from the terminals, ran onto the restricted airfield.
Police found no connection between the call and the man in the costume. They were investigating a report of loud noises that spurred the first call, Pedregon said.
What followed was pandemonium similar to an incident two weeks ago at JFK Airport in New York when a raucous celebration of an Olympics victory may have led to noises people believed were shots. The chain reaction turned into a panic as crowds bolted.
On Sunday, active shooter reports quickly spread on social media and word-of-mouth, and passengers in five terminals fled or pushed through security checkpoints, airport police said.
“We were on the jetway, and someone starts pushing behind us,” Jon Landis, a sales representative from Boston who was boarding a flight home, told The Associated Press. “One man was frantic, saying there was a shooter.”
Police officers, including one with a shotgun, eventually led passengers out of the terminal, through a security gate and into a parking lot, where several hundred people waited.
The scare created a mess, with three terminals shut down, roads closed and flights held in the air and on the ground, but no one was hurt.
About 280 flights were delayed, at least 27 planes diverted and two flights canceled, airport spokeswoman Nancy Castles said.
Officers with rifles stormed the airport but uncovered no evidence of a gunman or shots fired.
