Senior U.S. officials tell ABC News that in recent months there have been secret contacts between the Iranian government and the leadership of al Qaeda. It's a development that has caught the attention of top officials in the White House, the Pentagon and the intelligence community.
According to U.S. officials familiar with highly sensitive intelligence on this issue, the contacts are on the status of high-level al Qaeda operatives, including two of Osama Bin Laden's sons, who have been under house arrest in Iran since 2003. The officials don't believe Iran will allow these operatives to go free, but said they don't know Iran's motivation for initiating the talks.
"The Iranians know there would be hell to pay if these guys were set free," a U.S. official told ABC News.
"Iran likely sees these individuals, as major bargaining chips," says another official. "How and when they're going to use those chips or whether they are going to keep them in the bank is part of an ongoing strategic discussion they are having internally."
The fate of these al Qaeda operatives has been one of the most intriguing mysteries in the war on terror. Shortly after the U.S. invaded Afghanistan in late 2001, al Qaeda's central leadership broke into two groups. U.S. intelligence believes that one group, headed by Osama bin Laden and Ayman al Zawahiri, fled to the east to find safe haven in Pakistan's tribal areas. The second group, headed by an Egyptian named Saif al Adel, went west to Iran. This second group, which intelligence analysts say includes al Qaeda's management council, or "shura," includes about two dozen militants, including Adel, al Qaeda spokesman Suliman abu Ghaith and some of bin Laden's relatives, including two of his sons, Saad and Hamza.
Although U.S. officials rarely talk publicly about them, these militants are considered to be among the most dangerous terrorists in the world. Adel is on the FBI list of Most Wanted Terrorists and is a suspect in the 1998 bombings of the U.S. embassies in Kenya and Tanzania. The State Department has put a $5 million bounty on his head through the Rewards for Justice program; the only al Qaeda figures with higher bounties are Osama bin Laden and his deputy, Zawahiri.
Iranian authorities detained these militants in 2003, and they have been under what one U.S. official called "loose house arrest" in Iran ever since. The U.S. government quietly sent messages to Iran through the Swiss government, requesting that the al Qaeda figures be turned over to their native countries for interrogation and trial. Iran has refused.
In the past, the Iranians have also resisted efforts by al Qaeda to get the militants released. But recently there has been a renewed effort by al Qaeda to negotiate for their release and signs that the Iranians are willing to at least talk about that.
"Al Qaeda would like to get those folks a deal and they've been trying to work a deal," a senior defense official tells ABC News. "Right now there is greater effort being applied by al Qaeda to seek a resolution." Although Iran has recently signaled a willingness to discuss the issue, this official says, "I don't see the Iranian government desiring to work very fast or quickly on that. "
Buried inside the latest State Department report on terrorism, released in April, is one of the few on-the-record statements on this issue by the U.S. government.
"Iran has repeatedly resisted numerous calls to transfer custody of its AQ detainees to their countries of origin or third countries for interrogations or trial," the report says. "Iran also continued to fail to control the activities of some AQ members who fled to Iran following the fall of the Taliban regime in Afghanistan."
But U.S. officials tell ABC News that one reason they have not raised the issue more publicly is that they believe Iran has largely kept these al Qaeda operatives under control since 2003, limiting their ability to travel and communicate.
"It's been a status quo that leaves these people, some of whom are quite important, essentially on ice," said a U.S. official.
Iran has its own reasons to keep these militants under house arrest. Al Qaeda is a Sunni Muslim group that has a complicated, sometimes tense, relationship with Iran. Recent public statements by al Qaeda have taken an unusually anti-Iranian tone. In two audiotapes released last month, for example, Zawahiri lambastes the Iranian government for, among other things, trying to take over southern Iraq.
So, why would Iran now be reaching out to al Qaeda? U.S. intelligence analysts have several theories. Under one theory, the talks are a reaction to al Qaeda's recent anti-Iranian rhetoric. The Iranians are using the al Qaeda detainees as, the theory goes, leverage — "hostages" in the words of one official — to get al Qaeda to cut its recent anti-Iranian rhetoric and to deter any potential al Qaeda operations against Iran. By detaining them, Iran makes an unspoken threat to al Qaeda's leadership: If al Qaeda attempts to attack Iran, these people will suffer.
Others believe Iran may have initiated the talks as a threat to the United States, that if the U.S. takes hostile action against Iran, these captives could be released, set free to plot attacks against the West.
One senior U.S. official says there are ongoing "tensions and flirtations" between al Qaeda and Iran "with al Qaeda very much interested in trying to get these guys released and back in the fold, and with Iran playing strategic games knowing that al Qaeda is ultimately their enemy."
Adding to the concern about this, the intelligence community has only limited knowledge about the status of the al Qaeda operatives in Iran and even less about what Iran intends to do with them. Asked if the U.S. knows where Iran is holding them, a high-ranking U.S. military officer told ABC News, "No. I wish we did."
ABC News interviewed several high-level U.S. national security officials for this story. Because of the sensitive nature of intelligence on this subject, all spoke on the condition that their names not be used. We also asked the government of Iran to comment on this story. The spokesman for the Iranian Mission to the United States said he could not answer our specific questions but told us combating terrorism "remains one of the main Iranian political priorities."