The departures level at Los Angeles International Airport was closed to traffic Wednesday afternoon due to a report of a suspicious vehicle.
Police have cleared the vehicle that was causing closures and plan to allow guests back into affected areas. They will also end traffic diversions on all levels and roads.
Traffic was diverted to the lower arrivals level during the investigation. The airport asked travelers to allow for extra time.
Video showed a significant backup at the entrance to the terminal horseshoe road. Traffic on nearby roads was also backed up.
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"All vehicle traffic into the airport is impacted due to the police investigation, including Century and Sepulveda," LAX tweeted. "Shuttles are not currently running, including from economy parking. Please allow extra time and check your flight status. We will provide updates as available."
Passengers could be seen standing outside at least one terminal entrance on the upper level.
Details about the investigation were not immediately available.