Iran sentences Iranian-American businessman and father to 10-year imprisonment

Siamak Namazi, an international relations expert and business consultant, was arrested as he arrived in Tehran a year ago.

His father, former UN Children's Fund employee Baquer Namazi, was detained in February when he came to Iran to seek his son's release.

The elder Namazi was a governor of the Iranian province of Khuzestan before the Islamic revolution of 1979.

Mizan said three other people were also sentenced to 10 years for collaboration with the United States: Lebanese-American Nezar Zaka and two others identified only by the initials FHA and AA. 

State television reported Zaka's arrest in November 2015 on suspicion of having "numerous deep links to the US military intelligence community".

Baquer Namazi's former employer UNICEF issued a statement last month saying it was "deeply concerned about his health and well-being".

Video footage of his son's arrest was published by Mizan, which is linked to the judiciary, earlier this week.

It was presented with dramatic music alongside images of his US passport and shots of Washington Post journalist Jason Rezaian who spent two years in prison on espionage charges.

Rezaian was released in January at the same time as a nuclear accord with world powers came into force, lifting sanctions on Iran. 

Washington helped to airlift $400 million worth of Swiss francs and euros to Iranshortly afterwards - part of the money owed by the US because it cancelled defence sales at the time of the revolution.

The White House has denied accusations from hardline critics that this amounted to a hostage ransom for Rezaian and four others released at the same time.