The U.S. special operations forces who killed Osama bin Laden didn’t know for sure he was in a fortified villa near Islamabad until they swooped in and came face to face with the world’s most wanted terrorist.

While U.S. intelligence officers had concluded there was a “strong probability” bin Laden was living in the compound near the Pakistani capital Islamabad, all they could be positive about was that it was occupied by a high-value individual, unidentified officials said at a White House briefing. The military’s target was a specially built property in the city full of retired military 35 miles northeast of Islamabad.

The U.S. team was on site for less than 40 minutes, and bin Laden was killed resisting the assault, an official said. Three other men, one of whom may have been one of bin Laden’s sons, were killed in the raid along with a woman used as a human shield. Two women were injured. No other civilians or U.S. personnel were injured, said the officials, who spoke on condition there wouldn’t be identified.

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