(CNN) -- On December 15, 2001, Pakistani border troops came across some 30 al Qaeda fighters in a mountain pass. They had fled the U.S. bombardment of Tora Bora, Osama bin Laden's last stronghold in Afghanistan. The group turned out to be members of the al Qaeda leader's security detail, and U.S. intelligence swiftly dubbed them the "Dirty Thirty." They were transferred to U.S. custody in Kandahar and then moved to the Guantanamo Bay detention camp in Cuba early in 2002. It soon transpired most of the "Dirty Thirty" were from Yemen, a country where al Qaeda has an even greater presence today than it did before 9/11.
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WikiLeaks releases documents on al Qaeda detainees from Yemen
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Among the detainees are the "Dirty Thirty," part of Osama bin Laden's security detail
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Documents describe several religious institutes in Yemen as recruiters for al Qaeda
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-- A network of al Qaeda recruiters was able to operate in @placeholder with virtual impunity.
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Osama bin Laden
@placeholder planned to use Yemenis in the operation because they could easily travel to the region, according to another detainee.
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The Guantanamo documents suggest that Yemen remains a recruiting ground for al Qaeda, with one written in 2008 saying Yemeni sheikhs "continue to recruit Yemeni youth to participate in hostilities against @placeholder and coalition forces."