Two internationally renowned Iranian AIDS physicians were among four men sentenced to prison over the weekend for allegedly participating in a U.S.-backed plot to overthrow Iran's Islamic regime, Iran's state news agency reported Monday.

The prosecution of scientists Arash and Kamyar Alaei, who have been held in prison since June 2008, has raised an outcry among international human rights groups. The Alaei brothers and two others were tried in a closed-door trial last month.

The state news agency IRNA said Monday that the Alaei brothers and the two other defendants were convicted of recruiting dozens of others and planned to recruit more Iranian doctors, university professors and scientists to provide information to the U.S on Iran's infrastructure and civil defense.

"They aimed at creating social crisis, street demonstrations and ethnic disputes," the report quoted the general director of the counterespionage section of Iran's Intelligence Ministry as saying, without providing his name.

He said the CIA spent some $32 million on the plot and accused the U.S. of stationing intelligence agents in neighboring countries, such as the United Arab Emirates, Turkey, Kuwait and Azerbaijan.

IRNA initially announced on Saturday that four people had been convicted and sentenced in an alleged plot supported by the CIA and U.S. State Department, but it had not mentioned their names. Monday's report was the first confirming the Alaeis were among those convicted. Neither report said how long a prison term they had been sentenced to or identified the other two defendants.

The Alaei brothers' lawyer was not immediately available for comment.

They have run HIV/AIDS treatment and prevention programs in Iran, focusing particularly on at risk sectors like prostitutes and drug users. They have also held training courses for Afghan and Tajik medical workers.

Tension between the Washington and Tehran has been high in recent years over Iran's nuclear program and alleged support for Shiite militias in Iraq. The two countries have not had diplomatic relations since Iranian students took over the U.S. embassy in 1979 and held it for 444 days.