Southwest Flight 4236 arrived safely in Phoenix from Colorado Springs, Southwest Airlines said in a statement.
“Initial reports indicate that as the flight was arriving at the gate, an onboard customer exited the plane through a rear galley door,” Southwest Airlines spokesman Dan Landson said. “The flight captain stopped the plane and informed Air Traffic Control (ATC).”
It is not clear how the aircraft door was opened.
Phoenix Fire Station 19, which is located at the airport, was notified of the incident around 8 am, Phoenix Fire Brigade Captain Todd Keller said in a statement.
The man landed on the asphalt and headed for the fire station, entered the building and locked himself in a dormitory, Keller said.
“After a few minutes, the firefighters were able to persuade the adult male to open the door where he was then evaluated, treated and transported to a local hospital for a lower limb injury,” added the fire brigade captain.
Authorities responded to the incident, after which the flight “continued to its designated gate,” Southwest Airlines said.
A spokesperson for the Phoenix police told CNN that “I am aware of this incident and investigations are ongoing at this time.”
It is not clear whether the man will be accused.