(CNN) -- A single phone call by Osama bin Laden's trusted courier tipped off U.S. officials to his Pakistan compound, ultimately leading to the raid that killed the al Qaeda leader, a senior Pakistani intelligence official told CNN Saturday. The telephone call the courier made was "not the final one -- it was the initial piece of evidence" that sparked the focus on the compound in Abbottabad, the official said. Four years ago, U.S. officials uncovered the identity of a trusted bin Laden courier -- later identified as a Kuwaiti named Abu Ahmad -- whom they believed was living with and protecting the al Qaeda leader.
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NEW: U.S. officials release five edited videos found at bin Laden's compound
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Phone call was the "initial piece of evidence" leading to compound, Pakistani official says
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The phone call was made to an old friend by bin Laden's courier, Post reports
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Time of the phone call is unclear
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The Washington Post, citing @placeholder intelligence officials, reported Friday that Americans had intercepted a "catch-up phone call" Ahmad took from an old friend.
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The Washington Post, citing U.S. intelligence officials, reported Friday that Americans had intercepted a "catch-up phone call" @placeholder took from an old friend.
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"We have no information of any imminent terrorist threat to the @placeholder rail sector, but wanted to make sure our partners are aware of the alleged plotting.
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Questions remain over why and how @placeholder intelligence officials could not have known bin Laden was hiding out in the city, which is home to a military academy and has a strong military presence.