Southwest Airlines
A Southwest Airlines plane is seen at Los Angeles International Airport (file photo) Reuters

A Southwest Airlines flight was evacuated shortly before takeoff early on Tuesday (13 February) morning after a fire broke out on board.

Passengers and crew members onboard the Boeing 737 at John Wayne Airport in Santa Ana, Southern California, were told to disembark using the aircraft's front emergency slides just after the plane had pushed back from the gate.

According to CBS Los Angeles, smoke was detected in the cabin but all the 139 passengers escaped unscathed, save for some minor injuries as a result of going down the slides.

Allen Kenitzer, a spokesman for the Civil Aviation Authority, said the fire originated in the plane's auxiliary power unit, which provides power to start the aircraft's main engines and can be used as a backup source of power in some situations.

However, the blaze was quickly extinguished by the aircraft's suppression system.

The incident forced authorities at the airport to partially closed the taxiway occupied by the aircraft, although operations resumed as normal shortly afterward.

The incident comes after a tumultuous couple of days for Southwest Airlines, which on Sunday was forced to cancel hundreds of flights from Chicago's Midway International Airport due to a shortage of de-icing fluids.

"Throughout the storms, we've actively worked to manage our glycol levels [which is used to de-ice aircraft] but due to the severity of the winter weather Southwest has proactively cancelled about 220 flights as of midday Sunday," the airline told The Chicago Tribune.

The carrier had encountered a similar issue before Christmas, when it was forced to cancel approximately 90 flights as harsh weather conditions prevented its de-icing crews from servicing its planes.

The severe weather front that has hit Chicago grounded over 250 flights that were scheduled to leave Midway on Sunday.

The US's third-largest city has recorded measurable snow – when at least 0.1 of an inch occurs – for nine consecutive days between 3 and 11 February, matching a record last set in January 2009.