A Southwest Airlines pilot was removed from the cockpit ahead of a Wednesday flight from Georgia to Chicago and was booked on a charge of driving under the influence, a source familiar with the incident told CBS News.

The pilot allegedly smelled of alcohol and was removed by airport police before he flew Southwest Flight 3772 to Chicago from Savannah, Georgia, a source told CBS News. Photos shared online show cops removing him from the cockpit of the plane. Further details of what led to his arrest have not been released.

The U.S. Department of Transportation sued Southwest Airlines Wednesday, alleging it illegally operates flights that are persistently delayed, harming passengers and fair competition in the airline industry.

The pilot was later charged with driving under the influence, records from the local sheriff's office show.

A Southwest Airlines pilot was arrested at a Georgia airport and accused of DUI on Wednesday. A Transportation Security Administration officer smelled alcohol on the pilot and informed law enforcement officials, who arrested him at Savannah/Hilton Head International Airport, a source familiar with the situation told NBC News.

The Transportation Department said in a lawsuit that two of the airline’s routes were consistently delayed in violation of federal rules.

A Southwest Airlines flight was delayed multiple hours this week after a pilot was reportedly arrested and charged with DUI before takeoff in Georgia.

The pilot, David Allsop, 52, was arrested at Savannah Hilton Head Airport Wednesday morning and has been removed from duty. The flight was delayed about five hours.

Southwest Airlines and Icelandair signed a strategic agreement on January 15 to allow travelers to connect between the two airlines’ networks, with sales and travel through Baltimore (BWI) beginning in February. The partnership will also provide connections to Iceland from Nashville (BNA) and Denver (DEN) later this year.

SAVANNAH, Ga. (AP) — Police at a Georgia airport arrested an airline pilot on a DUI charge as he was making pre-flight checks aboard a Southwest Airlines flight with bloodshot eyes and reeking of what smelled like alcohol, according to a police report.

The Department of Transportation is suing the airline for what it characterized as months of "chronically delayed" flights — those that arrive at least 30 minutes late more than half the time.