Airport officials said in a press release that the "power bump" occurred at 6:29 p.m. Generators brought back most of the electricity immediately, but the equipment took some time to be restarted.
LAX Update: Due to an ongoing power disruption, @SouthwestAir has cancelled all remaining outbound flights from LAX this evening. All passengers will be advised to visit https://t.co/ZCrtG9fivB for rebooking info. #LAXalert— LAX Airport (@flyLAXairport) June 6, 2019
"Within the first hour, power was fully restored to Terminals 2, 3, 4, 5, 6 and Tom Bradley International Terminal. Operations in these terminals were not substantially impacted by the power disruption," the press release stated.
Officials had problems getting terminals 1, 7, and 8 immediately back online. The L.A. Department of Water and Power was on scene to fully restore power.
Southwest Airlines announced it canceled the rest of its flights for the evening. About 21 flights were canceled as a result, both departures and arrivals. Eighteen were Southwest and three were United flights.
Southwest passengers were advised to visit Southwest.com for re-booking information.
Terminals 7 and 8 were later fully restored, according to the airport.
LAX UPDATE: Terminal 7 power has been restored and systems are coming back online in that terminal. One @united flight was cancelled (Skywest 5510 to SBP), 7 diversions & 15 delayed flights. Call United customer service at 800-864-8331 or see ticket agent for more info. #LAXalert— LAX Airport (@flyLAXairport) June 6, 2019
United Airlines diverted most of its flights to San Francisco. Travelers can call United customer service at 800-864-8331 for more information.
Terminal 1 was the last terminal to be restored, according to the airport, but Southwest flights remained canceled.
By about 10 p.m. power had been restored to all terminals.
Both airlines anticipate normal operations on Thursday, the press release stated.
Throughout the outage, passengers reported being in darkness and some planes being deplaned via stairs.
"It's a bit bizarre. I've never seen this before," said passenger Eric Hamilton. "I come through LAX all the time, and I've never seen anything like it."
The long lines you usually see at security checkpoints were non-existent. Those trying to check-in were forced to wait on fold-out chairs.
The airport said that the disruption occurred due to a power bump at an "off-airport LADWP substation, which caused a power disruption throughout the airport."
Guests at terminal 1 were rescreened Thursday morning "out of an abundance of caution" due to the possibility people or luggage could have gotten past the terminal without being checked.
The incident triggered a massive backup of passengers waiting to be screened.