John Rizzo, who served as the acting general counsel for the agency, has admitted approving drone attacks inside Pakistan, beginning in 2004.
In February, Rizzo, who left the CIA more than a year ago, told Newsweek magazine he agreed to a list of people to be targeted by drone strikes, which started under the Bush administration.
"It's basically a hit list," Rizzo said. "The Predator is the weapon of choice, but it could also be someone putting a bullet in your head." A study by the New America Foundation, a Washington-based think tank, said 42 drone attacks were approved in four years.
The report said that the amount of strikes has quadrupled under the administration of US President Barack Obama and estimates about 2,500 people were killed in attacks on targets in Pakistan since 2004.
Arrest warrant
"There has clearly been a crime committed here," Clive Stafford Smith, a British human rights lawyer who is leading the effort to seek a warrant for Rizzo, told Al Jazeera.
"The issue here is whether the United States is willing to flaunt international law. More >>>
Location: Islamabad
