The Washington Post has expressed concern about the health of reporter Jason Rezaian, who has been in prison now for 500 days.

Jason Rezaian

Jason Rezaian

The U.S. daily has filed a new report with the UN indicating that the Post reporter “continues to lose weight; he suffers from blood pressure complications and other physical and mental medical conditions that remain untreated or poorly treated.”

Rezaian, who holds both U.S. and Iranian citizenship, was arrested along with his wife and two acquaintances in July of 2014 and is now charged with espionage. His wife and the other two detainees have been released.

Rezaian has attended four court sessions behind closed doors. His lawyer has said that no sentence has been handed down yet.

The Washington Post and the U.S. government have denied the accusations against Rezaian and have called for his immediate release.