U.S. Defense Dept.
This image of Khalid Shaikh Mohammed, the alleged mastermind of the Sept. 11 attacks, was released shortly after his capture in March 2003.
FBI Handout/Getty Images
This image of alleged Sept. 11 conspirator Ramzi Binalshibh was released after his capture — on Sept. 11, 2002.
The Pakistani government released this photo of Abu Farraj al-Libbi after his capture in May 2005. Al-Libbi has a skin disease that makes him easily recognizable.
Several suspected al-Qaida operatives accused of having ties to the Sept. 11 attacks were believed to be held at undisclosed locations overseas. Among them:
Khalid Shaikh Mohammed: The 9/11 Commission Report calls Mohammed the "principal architect" of the terrorist attacks of Sept. 11, 2001. He was captured in Pakistan in March 2003.
In February 2006, President Bush announced details of a plot that Mohammed had allegedly set in motion by October 2001 to fly an airplane into the U.S. Bank Tower, the tallest building in Los Angeles. Law-enforcement officials believe Mohammed also had a hand in the Bali nightclub bombings of October 2002, which killed more than 200 people, and in the murder of Wall Street Journal reporter Daniel Pearl.
Several media outlets have reported that the CIA has used a technique known as "waterboarding" — which involves simulating drowning — on Mohammed during interrogations. Testimony obtained from Mohammed was used in the Moussaoui trial.
Ramzi Binalshibh: Binalshibh is believed to have been the chief coordinator between al-Qaida and the Sept. 11 hijackers, and a member of the so-called "Hamburg cell" of conspirators. Binalshibh shared an apartment in Hamburg with Mohammed Atta, the suspected ringleader of the hijackers.
A Yemeni, Binalshibh was captured in Pakistan on Sept. 11, 2002 — exactly one year after the attacks. Testimony obtained from Binalshibh was used in the German trial of Mounir El Motassadek — the first person convicted in connection to the Sept. 11 attacks. Motassadek was convicted in August 2005 of belonging to a terrorist group and sentenced to seven years in prison.
Abu Zubaydah: A key al-Qaida lieutenant, Zubaydah was No. 3 on the United States' most-wanted list when he was captured in a safehouse in Pakistan in March 2002.
Zubaydah joined al-Qaida sometime in the 1990s, befriending Osama bin Laden and rising quickly up the ranks. The Saudi-born Palestinian was the terrorist organization's chief recruiter, helping to arrange training for new members. A Jordanian court sentenced Zubaydah to death in absentia for his role in a foiled plot to bomb hotels during celebrations of the millennium.
Abu Farraj al-Libbi: — Al-Libbi was captured in May 2005 following a gunbattle in Pakistan's northwest frontier region. After the arrest of Sept. 11 mastermind Khalid Shaikh Mohammed, al-Libbi is believed to have stepped in as head of operations for al-Qaida. Al-Libbi is suspected of planning at least two assassination attempts against Pakistani President Pervez Musharraf.