Key to the hunt was identifying the cell phone number of the courier and placing it under surveillance. In 2010, the U.S. intercepted a call to the courier in which he was asked where he had been. He responded that he was back with the people he had been with before. The caller then said, "May God facilitate you" - the implication being that courier was back with bin Laden and his family.
The courier did not make it easy to locate the compound, however, since every time he approached the compound, he turned off his phone. He did this more than 90 minutes out and removed the battery, so he went totally dark and would leave it off when he was in the compound. When he left the compound, he would wait 90 minutes and turn it back on. Analysts would therefore keep seeing this pop up in places all over Pakistan but nowhere near to Abbattabod. This is why it took so long to find the compound after they had the name and the cell phone number for the courier.
It took another two years after identifying the courier to find out what part of Pakistan Maulawi Jan operated in. Then, last August, the CIA discovered his residence. Officials said they were shocked by what they saw.
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