Al Qaeda’s leadership has reportedly set up cells of engineers to find ways to destroy and sabotage unmanned aircraft in an effort to curb the U.S. drone campaign against militants in the Middle East and North Africa.
U.S. intelligence officials have tracked the group's efforts to create a counter-drone strategy since 2010, according to secret intelligence documents obtained by the Washington Post from National Security Agency leaker Edward Snowden.
The classified report, titled "Threats to Unmanned Aerial Vehicles," consists of a summary of dozens of intelligence assessments posted by American spy agencies since 2006, The Post reported.
In July 2010, a U.S. spy agency intercepted electronic communications suggesting that senior Al Qaeda leaders had distributed guides to its operatives around the world on how "to anticipate and defeat" drones, according to the documents.
The Defense Intelligence Agency, or DIA, concluded that Al Qaeda was sponsoring research projects to develop technology to interfere with infrared tags and GPS signals on unmanned aircraft, The Post reported, citing the secret documents.
Still, the documents show that American spy agencies have concluded that Al Qaeda faces "substantial" challenges in its efforts to exploit the technological vulnerabilities of drones.
The Post reported that in 2011, the DIA reported that an “al-Qaeda-affiliated research and development cell currently lacks the technical knowledge to successfully integrate and deploy a counter-drone strike system.”
In Yemen, accelerated use of drone strikes under President Obama and a U.S.-backed offensive last year drove militants from territory they had seized a year earlier, during Yemen's political turmoil amid the Arab Spring.
While the U.S. acknowledges its drone program in Yemen, it does not usually talk about individual strikes. The program is run by the Pentagon's Joint Special Operations Command and the CIA, with the military flying its drones out of Djibouti, and the CIA out of a base in Saudi Arabia.
The U.S. drone program has caused extreme tension between Pakistan and the United States. Washington says it needs to use the unmanned aircraft because Pakistan refuses to engage fighters militarily.
Pakistan's foreign ministry on Saturday condemned a pair of suspected strikes that killed at least three foreign militants, calling them "unilateral" and a violation of Pakistan's sovereignty and territorial integrity.
"Pakistan has repeatedly emphasized the importance of bringing an immediate end to drone strikes," it said, describing the policy as counter-productive and responsible for the deaths of innocent civilians.
"Such strikes also set dangerous precedents in the inter-state relations," it added.
The Associated Press contributed to this report.