04:15 PM EST, 01/15/2025 (MT Newswires) -- Southwest Airlines ( LUV ) is allegedly operating multiple chronically delayed flights and disrupting passenger travel, the US Department of Transportation said in a lawsuit filed Wednesday in the US District Court for the Northern District of California.

The lawsuit seeks maximum civil penalties with chronic delays harming both passengers and fair competition, the agency said in a statement.

Delayed flights between Chicago Midway International Airport and Oakland and another between Baltimore and Cleveland resulted in 180 flight disruptions for passengers for five straight months starting in April 2022, the agency said.

"Airlines have a legal obligation to ensure that their flight schedules provide travelers with realistic departure and arrival times," US Transportation Secretary Pete Buttigieg said in the statement.

"Southwest ( LUV ) is disappointed that DOT chose to file a lawsuit over two flights that occurred more than two years ago," the airline said in an emailed statement to MT Newswires. "Since DOT issued its Chronically Delayed Flight (CDF) policy in 2009, Southwest ( LUV ) has operated more than 20 million flights with no other CDF violations."

"Any claim that these two flights represent an unrealistic schedule is simply not credible when compared with our performance over the past 15 years," Southwest ( LUV ) said. "In 2024, Southwest ( LUV ) led the industry by completing more than 99% of its flights without cancellation."