In her most forceful comments to date on the use of armed drones, the U.N.’s top human rights official, Navi Pillay, called their use “profoundly” disturbing.

Navi Pillay: “I also continue to be profoundly disturbed at the human rights implications of the use of armed drones in the context of counterterrorism and military operations, with an increasing number of states seeking to acquire such weapons. I urge all states to be completely transparent regarding criteria for deploying drone strikes, and to ensure that their use complies fully with relevant international law. Where violations do occur, states should conduct independent, impartial, prompt and effective investigations, and provide victims with an effective remedy.”

Pillay’s comments came during her opening address to the U.N. Human Rights Council in Geneva. During her remarks, she also renewed her call for the United States to close the military prison at Guantánamo Bay.

Navi Pillay: “I have repeatedly urged the government of the United States of America to close Guantánamo Bay in compliance with its obligations under international human rights law. I therefore acknowledge President Obama’s statement last Thursday outlining practical steps towards closing the detention facilities, such as the lifting of the moratorium on transferring relevant detainees to Yemen. I encourage the United States to ensure that all such measures are carried out in compliance with its obligations under international human rights law.”