(ABC NEWS) -- Attorney General Eric Holder has disclosed in a letter to Congress that four Americans were killed by U.S. drones in the course of the government's attacks on terrorists.
"Since 2009, the United States, in the conduct of U.S. counterterrorism operations against al-Qaida and its associated forces outside of areas of active hostilities, has specifically targeted and killed one U.S. citizen, Anwar al-Aulaqi," Holder wrote.
"The United States is further aware of three other U.S. citizens who have been killed in such U.S. counterterrorism operations over that same time period: Samir Khan, 'Abd al-Rahman Anwar al-Aulaki and Jude Mohammed. These individuals were not specifically targeted by the United States," Holder wrote.
Holder sent the letter to Senate Judiciary Committee Chairman Patrick Leahy, D-Vt., as well as to leaders of both parties in both houses of Congress, and the chairmen and ranking members of intelligence, foreign affairs and armed services committees. In the letter, Holder detailed U.S. policy on drone strikes against Americans.
The names of the Americans killed by drones had previously been classified information.
Samir Kahn was the publisher of Inspire magazine, which Anwar al-Awlaki edited. Abdul Rahman al Awlaki was Awlaki's son.
Jude Kenan Mohammed was on the FBI's 10 Most Wanted List and was believed to be plotting a car bombing on the 10th anniversary of 9/11.
The decision to target Anwar al-Awlaki was "subjected to an exceptionally rigorous interagency review" and approved by Holder and other Justice Department lawyers, Holder wrote.
Holder's letter, released before a speech by President Obama, represents the administration's most specific statement of policy on drone strikes against Americans.
The attorney general explained the criteria that made Awlaki, a radical Islamic preacher, a U.S. target. Killing him had a "definite military value," Holder wrote. He was not targeted for nonmilitary reasons, the "anticipated collateral damage was not excessive in relation to the military advantage," and the attack would not "inflict unnecessary suffering."
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