The 22 people who lived in the compound, many of them women and children, were caught by surprise but bin Laden and his men put up a fight.

"He was engaged in a fire fight with those that entered the house that he was in and whether or not he got off any rounds, I quite frankly don't know," said Brennan.

The SEALs cleared the smaller building first, killing the courier and his brother. They then moved to the main building where bin Laden and his family lived on the 2nd and 3rd floors. Bin Laden's son was killed and so was a woman, maybe bin Laden's wife, when the men tried to use her as a human shield.

"Here is bin Laden, who has been calling for these attacks, living in this $1 million-plus compound, living in an area that is far removed from the front, hiding behind women who are put in front of him as a shield," said Brennan.

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