WASHINGTON, Jan 15 (Reuters) - The Biden administration

on Wednesday sued Southwest Airlines ( LUV ), accusing the

carrier of illegally operating multiple chronically delayed

flights and disrupting passengers' travel.

The U.S. Transportation Department said in its civil suit

filed with the Justice Department that the carrier had operated

unrealistic schedules, and said it is seeking maximum civil

penalties. The department said Southwest ( LUV ) operated two

chronically delayed flights - one between Chicago and Oakland,

California, and another between Baltimore and Cleveland for five

months in 2022.

The department also said on Wednesday that it was fining

Frontier Airlines $650,000 for operating multiple

chronically delayed flights.