It happened at around 5:30pm at Nashville International Airport. A tire had either blown or collapsed. Three ambulances responded as a precaution.
It wasn't immediately clear if anyone was injured.
The FAA released a statement tonight, which reads, "Southwest Airlines 31, a Boeing 737 aircraft, rolled off a taxiway into the grass and got stuck while taxiing to its gate at Nashville International Airport at 5:30 pm Central Time. Passengers left the aircraft via stairs and were bussed to the terminal. The flight just landed from Houston Hobby Airport. The FAA is investigating."