NSA worked with CIA on drone strikes: The Washington Post

The controversial targeted killing program undertaken under the Obama administration as a counterterrorism measure relies heavily on intelligence gathered up by the National Security Agency, according to the latest revelations published by The Washington Post.

Based on documents leaked by former NSA contractor Edward Snowden, the report said the NSA was heavily involved in the drone campaign, previously thought to be the Central Intelligence Agency's realm.

The drone strikes rely "heavily on the NSA’s ability to vacuum up enormous quantities of e-mail, phone calls and other fragments of signals intelligence, or SIGINT," The Post reported.

"To handle the expanding workload, the NSA created a secret unit known as the Counter-Terrorism Mission Aligned Cell, or CT MAC, to concentrate the agency’s vast resources on hard-to-find terrorism targets," said The Post.

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The Post made sure to mention that it was withholding details about drone strikes that could potentially harm ongoing operations or national security at the behest of US intelligence officials.

The example it did provide was the targeted killing of an Osama bin Laden associate, Hassan Ghul, whom the United States has never publicly acknowledged killing.

The report came just two days after The Post published another article based on documents leaked by Snowden detailing how the NSA collected hundreds of millions of contact lists from around the world.

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The timing of the report also coincides with a study from the United Nations that warned against the use of drone strikes. UN rapporteur Christof Heyns, who submitted the report, focuses on extra-judicial, summary or arbitrary executions, according to the Guardian.

The report warned: "The use of drones by states to exercise essentially a global policing function to counter potential threats presents a danger to the protection of life, because the tools of domestic policing (such as capture) are not available, and the more permissive targeting framework of the laws of war is often used instead."

"Ours is a noble cause," NSA Director Keith Alexander was quoted by The Post as saying last month. "Our job is to defend this nation and to protect our civil liberties and privacy."

Alexander will reportedly step down early next year, though White House press secretary Jay Carney said his departure was not related to the Snowden leaks.

President Barack Obama defended the legality and rationale for the drone strikes in May 2013, saying, "Under domestic law, and international law, the United States is at war with al Qaeda, the Taliban, and their associated forces."

He added, "America does not take strikes when we have the ability to capture individual terrorists; our preference is always to detain, interrogate, and prosecute."