Iran's judiciary has confirmed that an appeals court has upheld 10-year prison sentences for a U.S. citizen, an Iranian-American businessman and his 81-year-old father, and a Lebanese citizen who holds a U.S. Green Card.
Tehran prosecutor Abbas Jafari Dolatabadi identified the four as Princeton University student Xiyue Wang, Iranian-American businessman Siamak Namazi and his elderly father, Baquer, and Lebanese technology expert Nizar Zakka, Iranian media reported.
The Washington-based lawyer of the Namazis, Jared Genser, said in late August that a Tehran appeals court had upheld the convictions days earlier.
The Namazis have been convicted of "collaborating with the hostile American government."
Earlier in August, Princeton University and the wife of Wang, a history doctoral student and U.S. citizen, said they had been informed that the Iranian authorities had upheld his jail term.
Wang was conducting research for his dissertation in Iran last year when he was detained by Iranian authorities and accused of "spying under the cover of research."
His family and the university have denied the charges.
Zakka was detained in September 2015 in Tehran after attending a government-organized conference on entrepreneurship in which he was a panelist.
He was later sentenced to 10 years in 2016 on espionage-related charges dismissed by his lawyer and family.
Wang and the Namazis are among a number of dual nationals held in Iran in what is believed to be a power struggle between the moderates and hard-liners who oppose any opening of the country following the 2015 nuclear deal with the international community on restricting Iran's nuclear program in exchange for sanctions relief.
Iran does not recognize dual nationalities.
In July, U.S. President Donald Trump warned that Iran faced "new and serious consequences" unless all "unjustly detained" U.S. citizens were released and returned.