LYNN NEARY, host: An Iranian who has been studying physics in Texas was put on trial in Tehran this week on charges related to espionage. He was arrested during a visit home in February, but his case only became public knowledge after Iran released two young Americans it had held for more than two years. NPR's Mike Shuster has the details.
MIKE SHUSTER: The student is Omid Kokabee. He is 29 years old, a graduate student at the University of Texas in Austin, studying optics. He went home to visit his family between semesters and when he failed to return to Austin, his friends discovered he had been jailed and charged with communicating with a hostile government and taking illegal funds.
When it became clear he would be put on trial, several organizations lodged protests. One of them, the American Physical Society, the largest group of physicists in the U.S., sent a letter to Iran's Supreme Leader, Ayatollah Ali Khamenei. Michele Irwin is the society's international programs administrator.
MICHELE IRWIN: He was just here in the U.S. to do his studies, just like many other Iranian students and other foreign students. And so the charges of him having communication with a foreign - you know, with an enemy government or receiving illegal funds was just kind of ridiculous, because this is something that many Iranian students are doing every day.
SHUSTER: Irwin said the letter explained that Kokabee was studying optics, not anything in the nuclear field, which has been such a sensitive issue between the U.S. and Iran. She read from the letter's appeal.
IRWIN: We are also concerned that such treatment of scientific personnel will discourage other Iranian science students from seeking the pursuit of knowledge abroad. Such studies ultimately serve to enrich the Iranian people and, of course, all of humanity.
SHUSTER: Just last month, Iran released the two American hikers who had been in prison for more than two years, charged with espionage. That came during the visit to the UN of Iran's president, Mahmoud Ahmadinejad. Ahmadinejad had offered to swap them for Iranians held in American jails, but the U.S. showed no interest. Just why the authorities in Tehran arrested Kokabee is not yet clear, says Abbas Milani, who is the director of Iranian studies at Stanford University.
ABBAS MILANI: There have been very little official announcement where one can sense what it is that they're after in this kind of an affair. But after the release of the two, there's been a lot of bickering and attacks and counterattacks from the judiciary, from the conservative camp against Ahmadinejad, and from Ahmadinejad against them.
SHUSTER: There was much criticism in the Iranian press aimed at Ahmadinejad and the judiciary, which oversaw the hikers case and required each to pay $500,000 to be released, says Muhammad Sahimi, who writes for the website Tehran Bureau.
MUHAMMAD SAHIMI: When the hikers were released, a lot of these mass media protested that why were they released, first of all, because they were convicted of spying. And second, why there were no negotiations to release the Iranians that are jailed in the United States.
SHUSTER: It is believed there are at least five Iranians serving prison terms in the United States on various charges of arms trafficking or other violations of economic sanctions. The criticism of the hiker affair has touched various political power centers in Tehran, especially the judiciary, says Abbas Milani.
MILANI: Even from some conservatives against the judiciary, saying that the way you played this out made us look like gangsters. To require them to pay 500,000 for what was allegedly a serious national security crime is absurd.
SHUSTER: Just how Omid Kokabee's case may intersect with these others is not clear, but it is in the hands of the judiciary, notes Muhammad Sahimi.
SAHIMI: I interpret it as more of a domestic type of issue, you know, trying to extract something from the guy and then in the process make some accusations either against Ahmadinejad or the reformists or one of these human rights groups, and so on.
SHUSTER: As with all these cases, it's unclear what the next step in the process is. Mike Shuster, NPR News.