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Security-conscious bin Laden's methods for undetected travel revealed

The wives and children of Osama bin Laden are taken to a chartered flight out of Islamabad after being deported to Saudi Arabia.

ISLAMABAD , Pakistan – One of the 17 letters seized during the 2011 U.S. raid on Osama bin Laden's Abbottabad compound and published Thursday reveals the lengths the al-Qaida chief went to keep himself and his family hidden and sheds light on how they apparently managed to remain undetected for so long while moving around Pakistan. 

The letter from bin Laden to “Sheik  Mahmud” was part of a cache of documents translated and released by the Combating Terrorism Center at West Point. A senior U.S. official told NBC News that "Sheik Mahmud" was actually Atiyah Abd al-Rahman, essentially bin Laden's chief of staff until he was killed in August 2011 by a CIA drone strike.

The letter is not dated, but analysts believe it was written between July 4 and Oct. 20, 2010. During that time, bin Laden would have been living in the Abbottabad compound where he was later killed, along with two of his wives -- Siham, a Saudi national, and Amal, of Yemeni origin -- as well as several children and grandchildren. His second wife, Khairiah -- also from Saudi Arabia -- had been under house arrest in Iran, along with other members of the bin Laden family, and was being released. 


In the letter, among several other topics, bin Laden issued detailed and complicated instructions as to how his wife -- referred to "Um Hamzah," or "mother of Hamzah" --  was to be moved to Pakistan and eventually reunited with him, if possible. Bin Laden showed a keen awareness of and great concern for the myriad ways in which she could be followed or tracked by intelligence elements and thus expose his location or those of other operatives.   

Once inside Pakistan, the letter said, she was to be taken "to the tunnel between Kuhat and Peshawar," where she should meet an al-Qaida contact and switch vehicles. "The meeting will be precise in timing and it will be inside the tunnel, and they will change cars inside the tunnel," he wrote, later explaining that moving through the tunnel was key to "avoiding surveillance." 

From there, he instructed the first car to "drive to an area that is unsuspected," while his wife in the second car would "go to Peshawar, go to one of the closed markets, and change cars again, then head to a safe place in Peshawar until we arrange for them to come, with Allah's will." Bin Laden even went so far as to consider the weather conditions, writing that the cars leaving the tunnel should "move after getting out of it in overcast weather, even if that would lead to them waiting for some time, knowing that the Peshawar area and its surroundings is often overcast." 

Read excerpts of the letter from bin Laden to 'Sheik Mahmud'

Bin Laden also warned of "the importance of getting rid of everything they received from Iran, like baggage or anything, even as small as a needle," concerned that tracking or listening devices could have been planted in clothes or other items in their possession. "Since the Iranians are not to be trusted, then it is possible to plant chips in some of the coming people's belongings," he wrote. 

It is unknown whether Khairiah's journey from Iran to Abbottabad actually followed this path, but her arrival at the compound, believed to have occurred in March or February 2011, reportedly caused many problems in the household. 

Brigadier Shaukat Qadir, a retired Pakistan Army officer who leveraged his military, intelligence, and tribal contacts to conduct an independent investigation into bin Laden's presence in Pakistan and the U.S. raid that killed him, was given access to the widows' interrogation transcripts, as well as the compound before it was destroyed. In his report, Qadir wrote that Khairiah was often at odds with other members of the household, particularly bin Laden's youngest wife, Amal, with whom he shared the third-floor living area, and bin Laden's son -- Khalid --  who also was highly suspicious of Khairiah's desire to join the family in Abbottabad. 

"Apparently," Qadir wrote, "he repeatedly asked her why she had come and, finally, on one occasion, (she) responded with a smile, "I have one final duty to perform for my husband.'" 

Qadir's theory is that Khairiahbetrayed her husband, leading authorities to him as she made her way from Iran. Bin Laden was killed in the U.S. raid within two or three months of her arrival.

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A Pakistani official, speaking on condition of anonymity, told NBC News she was "uncooperative" and "very difficult" during interrogations, acting aggressively towards the Pakistani authorities who questioned and held her for almost a year before she and the others were deported to Saudi Arabia last week. 

Previously, the only information available from family members about their movement came from an interrogation report of bin Laden’s youngest wife, Amal. Her testimony, which was summarized, described  how bin Laden and family members were moved quickly and frequently after 9/11 in an effort to keep them safe. She recalled being moved from place to place across the country, sometimes bouncing between multiple residences in a town or city. Her temporary homes ranged from the southern, mega-city of Karachi, to the crowded northwest capital of Peshawar, and the remote Swat Valley. 

Whether Qadir's theory proves true or not, the details and locations included in bin Laden's letter of instructions may provide clues as to how and where, exactly, he and his family moved around Pakistan for so many years, completely undetected.

Amna Nawaz is an NBC News correspondent in Pakistan.

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