WASHINGTON (Reuters) - The U.S. Department of Transportation fined Delta Air Lines $2 million for violating federal rules on passengers with disabilities, it said on Thursday.

The fine is the largest ever imposed against an airline in a non-safety related case.

The agency said it had found many violations of the requirements to provide assistance to passengers while getting on and off airplanes. The government also found Delta frequently did not respond adequately to disability complaints from passengers.

Most of the fine can be used by the airline to improve its service for travelers with disabilities, especially those in wheelchairs.

(Reporting by John Crawley; Editing by Lisa Von Ahn)

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