RIO DE JANEIRO (Reuters) - A Brazilian Air Force F-5 fighter jet crashed in the Rio de Janeiro metropolitan area shortly after takeoff on Thursday, but the two pilots ejected before the aircraft plummeted into a field, the Air Force said.

The refurbished fighter ran into trouble shortly after departing the Santa Cruz Air Force base west of Rio de Janeiro on a training flight, according to an Air Force statement. It said the jet crashed in an uninhabited area and no one was hurt on the ground.

The pilot and co-pilot of the twin-jet fighter were picked up and taken to the hospital for exams, as investigators inspected the crash site to find out what caused the accident, the Air Force said on Twitter.

The F-5 built by Northrop was first designed for use by the United States in the Korean war in the mid-1950s to face Russian Mig-15s. Brazil bought around 60 of the fighters in the 1970s and 1980s.

The refurbished F-5s have been the mainstay of the Brazilian Air Force since it retired its Mirage 2000s in 2013. It has been awaiting delivery of 36 Gripens from Sweden’s Saab AB.