U.S. police have arrested an American-born journalist working for Iran's English-language Press TV, the state-run broadcaster reported on Wednesday.
It said Marziyeh Hashemi was arrested at St. Louis Lambert International Airport on Sunday and was being held in custody in Washington DC. No formal charges had been made against her.
Federal Bureau of Investigation (FBI) officials were not immediately available for comment.
Hashemi, a TV anchor and documentary film maker, was in the United States to visit her family, the broadcaster said, and was allowed to call her daughter two days after her arrest.
According to Press TV, Hashemi was born Melanie Franklin in the United States and changed her name after converting to Islam.
She was quoted as saying by Press TV that she had been prevented from observing the Islamic dress code, hijab, in prison, and she was only offered pork as a meal, which is prohibited in Islam.
The only food she has had over the past two days has been a "packet of crackers," Hashemi was quoted as saying by Press TV.
Reuters could not independently verify this account of her treatment.
Hashemi had been living in Iran for more than a decade, various Iranian media said.
She has filed several reports on the subject of discrimination against women, Muslims, and African-Americans in the United States.