WASHINGTON –

In recent months there have been secret contacts between the Iranian government and the leadership of al-Qaeda, top officials in the White House, the Pentagon and the intelligence community said Thursday.

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Iran will allow these operatives to go free, but said they don't know Iran's motivation for initiating the talks.

"Iran likely sees these individuals as major bargaining chips," one official said. "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."

Shortly after the US invaded Afghanistan in late 2001, al-Qaeda's central leadership broke into two groups. US 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 went west to Iran, and intelligence analysts postulate that this group includes al-Qaeda's management council, or "shura," which numbers 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.

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 US embassies in Kenya and Tanzania. The State Department has put a $5 million bounty on his head.

Iranian authorities detained these militants in 2003, and they have been under what one US official called "loose house arrest" in Iran ever since. The US 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.

"Al-Qaeda would like to get those folks a deal and they've been trying to work a deal," a senior defense official told ABC News.

US intelligence analysts have several theories as to why al-Qaeda and Tehran have recently renewed contact. According to one theory, Iran initiated the talks as a threat to the United States; so that if the US takes hostile action against Iran, these captives could be released, and set free to plot attacks against the West.