Source:
The GuardianThe trail that led the CIA to Osama bin Laden began with his most trusted courier. It had taken the CIA years to discover first his name and then the home where he was hiding the al-Qaida leader. But it took only 40 minutes on Sunday for US special forces to kill both the courier and Bin Laden.Contrary to repeated speculation over the past decade that Bin Laden was living in one of the remote tribal areas of Pakistan or even across the border in Afghanistan, the al-Qaida leader was found in an affluent suburb of Pakistan's capital, Islamabad.
Senior US administration officials, briefing journalists in a late-night teleconference, said that after 9/11 the CIA chased various leads about Bin Laden's inner circle, in particular his couriers. One of these couriers came in for special attention, mentioned by detainees at Guantánamo Bay by his nom de guerre. He was said to be a protege of Khalid Sheikh Mohammed, the 9/11 mastermind, and one of the few couriers Bin Laden trusted.
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Two years ago, the CIA found the rough location where the courier and his brother lived in Pakistan, and on August last year they narrowed it down to a compound in Abbottabad, an affluent area about 35 miles north of Islamabad that had been founded as a British garrison town in the 1840s and named after its first deputy commissioner, Major James Abbott.more:
http://www.guardian.co.uk/world/2011/may/02/how-osama-bin-laden-found