Baquer Namazi, whose son Siamak has been held since October, was arrested on Tuesday, his wife wrote in a Facebook post. She said she was told he is now in Tehran's Evin prison.
"I must share the shocking and sad news that Baquer was arrested," Effie Namazi posted. "Now both my innocent son Siamak and my Baquer are in prison for no reason. This is a nightmare I can't describe."
Appearing at a Senate panel hearing yesterday, Secretary of State John Kerry said he was engaged on the matter but couldn't comment because of privacy considerations.
"We are aware of reports that a US citizen was detained in Iran," State Department spokesman Mark Toner said. "The US Department of State has no higher priority than the protection of US citizens overseas. We take our obligation to assist US citizens abroad seriously."
Haleh Esfandiari, a friend of the family and a Mideast expert at the Wilson Center, said Namazi is more than 80 years old and a dual US-Iranian national.
Namazi, she said, worked for the United Nations and at one point as a World Bank consultant, while also being a civil society activist. She described him as a "not at all political" person who consistently spoke out against US-led economic sanctions against the Islamic Republic.
The family lived outside New York for a period after the Islamic Revolution that toppled the US-backed shah in 1979, though later returned to Iran, she said.
Siamak Namazi, an Iranian-American businessman who similarly advocated a warmer US-Iranian relationship, is thought to have been arrested in October.
