In a secret CIA prison in Eastern Europe years ago, al-Qaida's No. 3 leader, Khalid Sheikh Mohammed, gave authorities the nicknames of several of bin Laden's couriers, four former U.S. intelligence officials said. Those names were among thousands of leads the CIA was pursuing.
One man became a particular interest for the agency when another detainee, Abu Faraj al-Libi, told interrogators that when he was promoted to succeed Mohammed as al-Qaida's operational leader he received the word through a courier. Only bin Laden would have given al-Libi that promotion, CIA officials believed.
If they could find that courier, they'd find bin Laden.
The revelation that intelligence gleaned from the CIA's so-called black sites helped kill bin Laden was seen as vindication for many intelligence officials who have been repeatedly investigated and criticized for their involvement in a program that involved the harshest interrogation methods in U.S. history.
"We got beat up for it, but those efforts led to this great day," said Marty Martin, a retired CIA officer who for years led the hunt for bin Laden.
Mohammed did not reveal the names while being subjected to the simulated drowning technique known as waterboarding, former officials said. He identified them many months later under standard interrogation, they said, leaving it once again up for debate as to whether the harsh technique was a valuable tool or an unnecessarily violent tactic.
