|Rizzo told Newsweek that he was the person who signed off on the CIA's lethal operations [GALLO/GETTY]
Human rights lawyers in the UK and Pakistan are seeking the arrest of the Central Intelligence Agency's (CIA) former legal director for approving drone strikes that killed hundreds of people.
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.
"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.
"One of the purposes of doing this is because there is no sense in the United States of how catastrophic this whole process is."
US government lawyers argue that drone strikes are conducted on a "solid legal basis", however, Stafford Smith said there has to be a war going on in order for any of these strikes to be legal.
"Outside a combat zone the US has no possible, plausible legal basis to conduct these drone strikes. They think they can get away with it. This process is meant to make sure that they can't," Stafford Smith said.
"I challenge anyone to go to the families of those innocent victims in the [Afghanistan-Pakistan] border regions and say: 'It's legal to bomb your homes and kill your children'. It is not, obviously."
In May 2010, the CIA was granted approval by the US government to expand drone strikes in Pakistan's tribal regions in a move to step up military operations against Taliban and al-Qaeda fighters.
Federal lawyers backed the measures on grounds of self-defence to counter threats the fighters pose to US troops in neighbouring Afghanistan and the US as a whole.
The US announced that targets would include low-level combatants, even if their identities were not known.
Obama had previously said drone strikes were necessary to "take out high-level terrorist targets".