"The aircraft's two pilots were killed in the accident which took place this morning in Anarak district," the broadcaster's website said.

The fighter jet was on a training mission when it crashed, the province's deputy governor Mohammad-Reza Jannessari told the official IRNA news agency.

An investigation has been opened into the cause, he added.

The Iranian air force has suffered several crashes in recent years. Officials have complained of difficulties in acquiring spare parts to keep its ageing fleet in the air.

In February, an Iranian F-5 jet crashed in a residential area of the northwestern city of Tabriz killing three people, including its two-man crew.

Iran has mostly Russian MiG and Sukhoi fighter jets that date back to the Soviet era, as well as some Chinese aircraft, including the F-7.

Some American F-4 and F-5 fighter jets dating back to before the 1979 Islamic revolution are also part of its fleet.