MICHELE NORRIS, host:
Now a puzzling twist in the mystery of a former Iranian general who is believed to have defected to the U.S. or Israel. The man in question is a former high ranking officer in Iran's elite revolutionary guard, who left Iran three years ago and turned up in Istanbul. It's believed he possessed valuable information that the government of Iran would not want shared with the CIA. Late last month, the claim emerged that he had died in an Israeli prison.
But as NPR's Mike Shuster reports, no one's sure what to believe.
MIKE SHUSTER: His name is Ali Reza Asgari, and Iran experts believe he possessed valuable information on Iran's secret nuclear activities and on its relationship with Hezbollah in Lebanon.
In late 2006, Asgari left Iran, apparently without authorization, says Meir Javedanfar, an Israeli specialist in Iranian affairs.
Mr. MEIR JAVEDANFAR (Iranian Affairs Specialist): He went to Syria, crossed the border into Turkey, and he disappeared into thin air.
SHUSTER: Asgari apparently put himself into the hands of the CIA or the Mossad, Israel's secret service, says Karim Sadjadpour, who follows Iran for the Carnegie Endowment for International Peace.
Mr. KARIM SADJADPOUR (Associate, Carnegie Endowment for International Peace): For the CIA or for the Mossad, someone like Ali Reza Asgari would really be a treasure trove of information.
SHUSTER: In the three years since his disappearance, reports have surfaced that Asgari provided information on a secret uranium enrichment site in Iran and that he also provided information that led to the Israeli bombing of a possible nuclear site in Syria in 2007.
Asgari had been for many years the key Iranian liaison with Hezbollah in Lebanon, and it is likely he provided much information on Hezbollah, including on one of its most dangerous characters, Imad Mughniyah. Mughniyah was probably behind a number of devastating terrorist attacks on U.S. targets in Lebanon. He himself was killed by a car bomb two years ago in Syria, and it has been suggested that Asgari provided information that helped his assassins.
Why did Asgari, such a key figure in Iran's Revolutionary Guard, defect? The answer may be simple. When he returned to Iran from assignments in Lebanon, this would've been a decade or so ago, he was thrown in jail, says Karim Sadjadpour, and accused of moral corruption.
Mr. SADJADPOUR: And he was also accused of financial corruption. That he was skimming off the top in various arms deals. And he was brutally tortured when he was in prison.
SHUSTER: According to some who know Asgari, it was after this torture that he decided to break with Iran's government. Little is known of what happened to Asgari after he surfaced briefly in Turkey three years ago. But those following this case assumed he was taken somewhere in the U.S. So it was a surprise when a report posted on the Internet in late December, citing a source in Israel's defense ministry, asserted that Asgari died in an Israeli prison cell, either by his own hand or murdered by the Israelis.
Karim Sadjadpour is skeptical.
Mr. SADJADPOUR: The idea that he would either have committed suicide or died in an Israeli prison doesn't make any sense to me, especially if you're operating under the assumption that this was someone who was extremely disaffected, that he defected on his own, he wasn't kidnapped or lured. And he was a very important source of information. There's no need to kill someone who is openly cooperating and providing you information.
SHUSTER: But this story was taken up by the news media in Iran, and the Iranian government asked the United Nations and the Red Cross to help bring Asgari's body back to Iran.
Meir Javedanfar does not believe Asgari died in Israel, and he has his suspicions about the Iranian government's motives.
Mr. JAVEDANFAR: They are trying to use this story in order to get - even if there's a little bit of clue as to what happened to him, because they're probably worried that if they don't know what happened to Asgari, tomorrow, another official could disappear the way Ali Reza Asgari did. And they would probably want to prevent that by knowing what happened to Mr. Asgari in the first place.
SHUSTER: There have been other cases. One nuclear scientist who defected to the U.S. but then returned last year to Iran, he has reportedly been imprisoned in Tehran. And several individuals connected to Iran's nuclear program have been killed by car bombs over the past year. Asgari's is hardly an isolated case, says Karim Sadjadpour.
Mr. SADJADPOUR: I think that there are dozens of individuals within the Iranian government who are extremely disaffected. And the Iranian government recognizes it's vulnerable to these types of defections.
SHUSTER: Given the difficulties Iran's nuclear program has recently experienced, the clandestine efforts to disrupt the program may just be paying off.
Mike Shuster, NPR News.