WikiLeaks: Bin Laden's courier 'trained 9/11 hijack team'
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For the past two years, American spies had been monitoring the courier, known as Abu Ahmed al-Kuwaiti, after learning his name four years ago, according to US officials.
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The file for the Guantanamo detainee, Muhammad Mani al-Qahtani, who was to have been the "20th hijacker" on 9/11, contains a reference to the key US intelligence thread that led directly to bin Laden.
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The file suggests that the courier’s identity was provided to the US by another key source, the al-Qaida facilitator Hassan Ghul, who was captured in Iraq in 2004 and interrogated by the CIA.