The Namazis were convicted of “collaborating with an enemy state” — meaning the United States — but the precise nature of the charges against them were never made clear.
They are among at least four Americans incarcerated in Iran, three of them citizens of Iranian descent. Iran, which does not recognize dual citizenship, considers the Namazis to be Iranian citizens, with none of the consular rights afforded to foreigners.
The prosecution of the Namazis in Iran partly reflects deep-seated suspicions by its judicial authorities about Americans of Iranian descent who come back to visit. A number of them have been imprisoned on charges of spying or sedition or both.
The Namazi family in particular has been singled out. Siamak Namazi, 45, spent much of his life in the United States and became a prominent public policy scholar and business executive who advocated improved ties with Iran. He was arrested in October 2015 while visiting relatives in Iran.
His father, 81, is a former Unicef representative. He was arrested four months later, after he returned to Iran to check on his son.
Credit Leonhard Foeger/Reuters
Mr. Genser and other advocates for the Namazis have said the health of both father and son have deteriorated in Evin Prison, where both have been held in separate cells.
The father, a triple-bypass heart patient, has lost 30 pounds in prison, and suffers shortness of breath, dizziness, confusion and hearing loss, Mr. Genser said. The son has spent much of incarceration in solitary confinement, the lawyer said, and has “been interrogated relentlessly, beaten and tased.”
The denial of the father’s appeal, in particular, amounted to a rejection of pleas by United Nations officials, including Secretary General António Guterres, to show leniency toward a former Unicef diplomat. In a statement, Unicef said it was “deeply saddened to learn that the appeal of the 10-year prison sentence of Baquer Namazi, our respected former colleague, has been denied.”
The Iran Mission to the United Nations did not immediately respond to a request for comment. News of the rejected appeal was not reported in Iran’s official media.
The other Americans known to be held in Iran include Karan Vafadari, a dual citizen who is a Tehran art gallery proprietor; and Xiyue Wang, a Princeton University graduate student in history who was arrested last year while researching public records in Iran for his doctoral thesis. A fifth American, Robert Levinson, has been missing in Iran for 10 years.
News of Mr. Wang’s arrest was not publicly disclosed until last month, when Iranian prosecutors announced that he had been sentenced to 10 years in prison on spying charges.
Princeton, which had known about Mr. Wang’s arrest and broke its silence after Iran announced his conviction, has called the charges baseless. Academic officials in the United States have said Mr. Wang’s incarceration was likely to chill what remains of any scholarly exchanges with Iran.
Earlier this month, Princeton said the Iranian authorities had denied Mr. Wang’s appeal. In a statement, the university reiterated that Mr. Wang was “not involved in any political activities or connected to any government agencies; he was simply a scholar conducting historical research.”
Iran also is holding other foreign citizens accused of conspiring against the government.
They include Nazanin Zaghari-Ratcliffe, a British-Iranian employee of the Thomson-Reuters Foundation, who has been sentenced to five years in prison on charges of plotting sedition while traveling in the country with her young daughter; and Nizar Zakka, a Lebanese citizen, who is a permanent resident of the United States and an information technology expert. He was arrested while attending a conference in Iran and sentenced a few months ago to 10 years in prison on spying charges.
Jason I. Poblete, Mr. Zakka’s lawyer in the United States, said Monday that his client’s appeal also had been denied.
Mr. Poblete issued a statement quoting his client as saying: “If you’re traveling to Iran on business or pleasure, let my case be a lesson and a warning.”