A U.S.-based human rights group says the Iranian government should cancel a broadcast scheduled for later Wednesday in which two Iranian-Americans supposedly confess to spying.
Human Rights Watch expressed concern that Iranian authorities used coercive means to compel Haleh Esfandiari and Kian Tajbakhsh to make incriminating statements.
Tuesday, the United States called on Iran's leadership to treat the two detained Iranian-Americans with "the respect they deserve."
The State Department said it is appalled at what it called the mistreatment of the two prisoners after footage of them was shown promoting Wednesday's show called "In the Name of Democracy."
Tajbakhsh is a New York-based urban planning consultant at the Open Society Institute of philanthropist George Soros.
Esfandiari is a Middle East expert at the Washington-based Woodrow Wilson International Center for Scholars.
The U.S. State Department says Washington is outraged by the detentions. It says the two have worked for years to build bridges of understanding between Iran and the United States.
Another Iranian-American, peace activist Ali Shakeri, also is being held in a Tehran prison. A fourth, journalist Parnaz Azima, has been prevented from leaving Tehran.
The United States has denied any of the four are involved in spying.
Iran, which does not recognize dual nationalities, has told the United States the cases of the four are none of its concern.
Some information for this report was provided by AFP.