Pakistan's Foreign Ministry records have confirmed that of some 2,200 people killed by drone strikes in the past decade, at least 400 were civilians and an additional 200 victims were deemed "probable non-combatants," Ben Emmerson, UN special rapporteur on human rights and counterterrorism stated on Friday.

According to the UN special rapporteur, Pakistan's Foreign Ministry had recorded at least 330 drone strikes in the federally administered tribal areas, bordering Afghanistan, since 2004.

Most, but not all, attacks with unmanned aerial vehicles have been by the United States. Britain and Israel have also used them.

"Officials indicated that, owing to underreporting and obstacles to effective investigation, those figures were likely to be an underestimate" of civilian deaths, Emmerson said.

"The involvement of CIA in lethal counter-terrorism operations in Pakistan and Yemen has created an almost insurmountable obstacle to transparency," Emmerson added.

"One consequence is that the United States has to date failed to reveal its own data on the level of civilian casualties inflicted through the use of remotely piloted aircraft in classified operations conducted in Pakistan and elsewhere."

Emmerson urged the United States to declassify to the maximum extent possible information "relevant to its lethal extraterritorial counter-terrorism operations; and to release its own data on the level of civilian casualties inflicted through the use of remotely piloted aircraft, together with information on the evaluation methodology used."

Washington uses assassination drones in several countries as part of its targeted-killing program, claiming that they target “terrorists.” According to witnesses, however, the attacks have mostly led to massive civilian casualties.

Some former US terror-drone pilots have confirmed the regular killing of civilians during the deadly strikes.

RA/