( CNN ) -- The operation that led to the killing of al Qaeda leader Osama bin Laden took shape after detainees identified a trusted bin Laden courier as someone who may have been living with and protecting the militant leader , senior administration officials said . That courier became a key lead in locating bin Laden , the officials said . The officials provided details on the origins of the operation and the raid that led to bin Laden 's killing : . • Four years ago : Officials uncovered the courier 's identity . • Two years ago : Investigators identified areas of Pakistan where the courier and his brother lived . • August : The residence of the courier and his brother was found in Abbottabad , 30 to 35 miles north of Islamabad , Pakistan 's capital . • September : The CIA worked with President Barack Obama `` on a set of assessments that led it to believe that in fact it was possible '' bin Laden may be at the compound in Abbottabad . • February : U.S. officials concluded there was a `` sound intelligence basis '' for pursuing bin Laden at that location . • March and April . Obama held a series of National Security Council meetings `` to develop courses of action to bring justice to Osama bin Laden . '' There were at least five meetings : March 14 , March 29 , April 12 , April 19 and Thursday . • Friday . Obama gave the final order to pursue the operation . How U.S. forces killed Osama bin Laden . • Sunday . After months of decision-making and planning , a U.S. military team conducted a small helicopter raid on the compound . The officials did not provide a breakdown of team members , but a senior U.S. defense official said U.S. Navy SEALs were involved in the operation . The senior administration officials provided these details of the raid : . • The team was in the compound for 40 minutes . It did not encounter any local authorities during the raid . • Bin Laden resisted the assault force and died in a firefight . Along with bin Laden , three adult males were killed . • Two were believed to be the couriers , and one was a son of bin Laden 's . Trail leading to bin Laden began with his trusted courier . • A woman used as a human shield by a male combatant died , and two women were injured . • A helicopter was lost because of mechanical failure . • Intelligence on bin Laden was not shared with Pakistan and other countries . • After the raid , U.S. officials briefed Pakistani and other world leaders . • Bin Laden has been buried at sea and his body was handled in the Islamic tradition . The officials but did not elaborate .
Information from detainees started the chain of events that led to the raid . A trusted Osama bin Laden courier was a key to locating bin Laden . U.S. officials concluded in February the information on bin Laden was `` sound ''