Plane returns to airport after baggage found unscreened

Luggage lies on the tarmac outside a Spirit Airlines jet on Friday.

LOS ANGELES, California (CNN) -- A Spirit Airlines jet returned to Los Angeles International Airport Friday after the pilot learned that some of the luggage on board had not been properly screened, officials said.

Soon after Flight 923 took off shortly after noon, an airline worker "realized that nine bags had gone on the plane without being checked," said Laura Bennett, a spokeswoman for the airline. The worker told a supervisor who ensured that the pilot was alerted.

The MD-80, en route to Detroit International Airport, was 90 minutes into the flight -- over Nevada -- when the error was discovered, said LAX spokesman Tom Winfrey.

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The pilot alerted the Federal Aviation Administration, which ordered him to return to LAX, Bennett said.

The jet was ordered to a remote runway, where the 89 passengers and six crew members deplaned, said Bennett.

Airline screeners and police bomb squads using dogs examined the luggage as a precaution and found nothing unusual, she said.

The plane was to set out again momentarily.

Spirit Airlines is the largest privately held airline in the United States, with about 100 daily flights in 15 markets.