Tehran (dpa) - Iranian authorities have freed Washington Post reporter Jason Rezaian in a prisoner swap deal, Iran's semi-official Fars news agency reports, citing the prosecutors.

Rezaian, who was taken into custody in July 2014 and convicted on espionage charges last year, was one of four Iranian-American nationals held by Iran to be released under the deal.

In exchange, the US will release six Iranian-Americans it had jailed, the Fars report said.