A letter to bin Laden from his chief of staff dated 11 June 2009 has a detailed account about a group of "mid level" al Qaeda members who the Iranians had recently released, including three Egyptians, a Yemeni, a Iraqi and a Libyan.

Bin Laden's chief of staff attributed these releases to al Qaeda's kidnapping of the Iranian diplomat in Peshawar, but added that the Iranians "don't want to show that they are negotiating with us or reacting to our pressure. ... We ask God to repel their evil."

In another undated letter from bin Laden to his chief off staff al Qaeda's leader gave a set of detailed instructions about how best to handle his family members living in Iran once they were released.

Bin Laden urged extreme caution "since the Iranians are not to be trusted." Among another precautions, he wrote that his family members "should be warned about the importance of getting rid of everything they received from Iran like baggage or anything even as small as a needle, as there are eavesdropping chips that have been developed to be so small they can be put inside a medical syringe."

In this letter bin Laden mentioned by name a number of his children living in Iran including his sons Ladin, Uthman and Muhammad and his daughter Fatima, who is married to Sulaiman Abu Ghaith who now sits in a Manhattan jail.

In October the U.S. Treasury named as terrorists six al Qaeda members living in Iran who it said are funding terrorist activities in Pakistan and sending fighters and money to Syria to fight the Assad regime there.

Abu Ghaith didn't play an operational role in al Qaeda -- a fact that was underlined in the charges filed against him last week in Manhattan that revolve around his role as a propagandist for the group. So it is the precise nature of al Qaeda's arrangements in Iran and the kind of activities outlined in the recent Treasury designation of the half-dozen al Qaeda members living in Iran that are likely to be of most interest to American investigators.

Given the fact that since 9/11, New York courts have convicted at a rate of 100% in cases that involve members of al Qaeda and associated groups, Abu Ghaith could doubtless cut an attractive plea deal for himself if he gives a full accounting of al Qaeda's murky decade in Iran.

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