WASHINGTON - United Airlines says it is investigating after a vendor employee was found unharmed in an aircraft’s cargo hold following a flight from Charlotte, North Carolina, to Washington Dulles International Airport.

The airline said in a statement to The Associated Press on Monday that United Express flight 6060 operated by Mesa Airlines landed safely at Dulles on Sunday.

The statement says once at the gate, an employee of the airline’s ground handling vendor was found in the cargo area. The employee wasn’t identified.

A spokeswoman for the Metropolitan Washington Airports Authority directed questions to United.

CBS Charlotte affiliate WBTV reports the employee who got trapped was a baggage handler. WBTV reports radio traffic reveals the handler refused medical treatment, and that airport officials weren’t sure whether it was a security incident or an accident.

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