An American Airlines flight departing from Denver Airport issued a forced evacuation when the plane experienced an issue with its landing gear while on the runway.

Flight AA3023 bound for Miami, Florida, was preparing for takeoff when first responders were alerted about the issue on Saturday afternoon and evacuated everybody onboard the Boeing 737 MAX 8.

Video posted online showed all 173 passengers and six crew members frantically exiting the plane on a slide as smoke billowed from underneath the aircraft.

Five people were treated at the scene, while a sixth was transported to a local hospital for what has been described as a minor injury.

The plane had been scheduled to depart from Denver at 1.12pm, and the FAA said that a 'possible landing gear' incident happened during takeoff on runway 34L.