The CIA tracked bin Laden to a five-year-old palace compound custom-built for bin Laden and protected by 12- to 18-foot walls topped by barbed wire, owned by two brothers in a rich suburb of Pakistan's capital, Islamabad, last September, senior Obama official told a group of us news people in a midnight conference call (Update: Click for a transcript from of the call.)

The suburb, Abbottabad, is home to retired Pakistani military officers, one official said, adding the mansion where bin Laden stayed was by far the biggest house in a neighborhood of comfortable homes.
Another official said suspected al Qaeda supporters detained by the US had told US authorities a courier they were tracking was working with bin Laden, but al Qaeda security made it tough to nail his location until last summer, when US officials figured the large size and extraordinary security at the compound made it likely bin Laden was there.
By February the CIA and other agencies felt they had enough information to plan an attack. Starting in March, the agencies began planning an attack, and the attack was authorized April 29.
A third official defended the attack, calling bin Laden a key figure in targeting the US as a target by supporters of his al Qaeda movement ten years after the 9/11 attacks. Some analysts have said he didn't appear to have direct control over today's Islamist terrorists but still served as an inspiration.
Three other men were killed in the 40-minute raid, including two suspected couriers and a son of bin Laden. A woman was killed when she was used by one of bin Laden's companions as a human shield, an official said. One of the raiders' helicopters broke down, but all the US raiders were able to leave safely, with bin Laden's dead body.
Pakistan wasn't told of the raid, officials said, without explaining how this squares with Obama's statement earlier this evening that "cooperation with Pakistan helped lead us to bin Laden."
The US is claiming it had both legal and moral obligations to attack bin Laden. One official warned there may be increased danger to Americans from retaliation by al Qaeda supporters. Bin Laden deputy Ayman al-Zawahiri, born in Egypt, is expected to take over as al Qaeda boss. An official said bin Laden's body would be treated in accordance with Islamic law.
What US officials aren't saying: Why didn't Pakistan, nominally our ally, act against bin Laden long ago?
(Update: From Abbotabad)