Usama bin Laden's son isn't the only Al Qaeda operative believed to have been killed in an attack by an unmanned U.S. drone in the past year.

U.S. officials tell FOX News that Saad bin Laden, who is not considered a significant player in Al Qaeda leadership, was "collateral" damage in an airstrike in Pakistan and was not considered important enough to target on his own.

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But other high-value operatives, some of them with key roles in Al Qaeda, also have been taken out by U.S. attacks. The following are 10 top operatives killed in the past year:

Khalid Habib — veteran combat leader and operations chief involved with plots to attack the West; deputy to Shaikh Sa'id al-Masri, Al Qaeda's No. 3.

Rashid Rauf — mastermind of the 2006 transatlantic airliner plot.

Abu Khabab al-Masri — Al Qaeda's most seasoned explosives expert and trainer, and the man responsible for its chemical and biological weapons efforts.

Abdallah Azzam — senior aide to Sheikh Sa'id al-Masri.

Abu al-Hassan al-Rimi — led cross-border operations against Coalition forces in Afghanistan.

Abu Sulaiman al-Jaziri — senior external operations planner and facilitator.

Abu Jihad al-Masri — senior operational planner and propagandist.

Usama al-Kini — Marriott attack planner and listed on the FBI's terrorist most wanted list.

Sheikh Ahmed Salim Swedan — involved in the attacks on the US Embassies in Kenya and Tanzania.

Abu Sulaiman al-Jaziri — senior trainer and external operations plotter.

FOX News' Catherine Herridge contributed to this report.