The raid occurred in a span of 38 minutes early Monday morning, following CIA reports of repeated sightings of a tall man doing "prison yard walks" around the yard of the housing compound in Abbottabad, which was under constant surveillance, this official said. U.S. authorities never definitely determined beforehand that this man was in fact bin Laden, but they eventually concluded that there was enough evidence to go through with the operation.
The first man killed in the mission -- which this official said was code-named "Operation Neptune Spear" -- was the Kuwaiti courier who had worked for bin Laden. He was shot dead after a brief gunfight in a guesthouse. From that point on, it's believed no other shots were fired at the U.S. forces, the official said.
The troops then moved into the compound's main three-story building, where they shot and killed the courier's brother. As they moved upstairs and around barricades, one of bin Laden's sons rushed at them and was subsequently killed, according to this latest account. Neither of these men had weapons either on them or nearby, this official said.
The U.S. official said that the team then entered the third-floor room where bin Laden was, along with his Yemeni wife and several young children. The al Qaeda leader was moving, possibly toward one of the weapons that were in the room, when he was shot, first in the chest and then in the head. He never had a gun in hand but, like the other men, still posed an imminent threat, according to the official.
Afterward, one SEAL laid down beside the dead bin Laden to measure his height and further determine that he, in fact, was the man who for years has ranked atop the FBI's "Most Wanted Terrorists" list.
Interesting inclusion of that last detail there - I'm sure they didn't foresee a need to ID him after the fact and just neglected to bring a measuring tape or a bit of twine or something. If the photos leak, no way was it someone posing with the corpse for a trophy photo at all.
http://www.cnn.com/2011/WORLD/asiapcf/05/05/bin.laden.main/index.html