Iran released four Americans from custody, including the Washington Post's Tehran correspondent Jason Rezaian, who had been held since July 2014 on spy charges.

Also freed were former U.S. MarineAmir Mirza Hekmati, who Iran accused of spying for the CIA, ranian-American Christian pastor Saeed Abedini and Nostratollah Khosravi. All four had dual US-Iranian citizenship.

CNN reported that U.S. diplomatic sources confirmed the release.

The prisoner release comes just hours before a United Nation's watchdog group was to announce if Iran was complying with the nuclear deal reached between the United States and Iran last July.

Tehran Prosecutor Abbas Jafari Dolatabadi said in a written statement that the release waspart of a prisoner exchange agreement with the United States. The U.S. government has not yet commented or confirmed.

The release was reported Saturday, January 16, 2016 by Iran's Naim news outlet. Naim, which is aligned to Iranian hard-liners, reported that seven unnamed Iranian-Americans held in U.S. jails are being freed in exchange. Iranian news reports have referred to Iranians held by the U.S. on charges related to violating sanctions against Iran.

The Iranian news agency IRNA reported the United States released seven Iranians. The report cited an unnamed source identifying those freed by the United States as Nader Madanlou, Bahram Mekanik, Khosro Afghahi, Arash Qahreman, Touraj Faridi, Nima Golestaneh and Ali Sabounchi as the seven Iranian nationals who have been released.

#Photos: #Iran's @JZarif meets #US Secretary @JohnKerry in #Vienna https://t.co/JncV5nizSj #ImplementationDay pic.twitter.com/ti0HZeDEYe

-- Iran (@Iran) January 16, 2016