In-depth coverage of the debate over unmanned aerial vehicles
Both reports conclude that in many cases, drone strikes may have breached international laws. Both also say the White House's and CIA's lack of transparency surrounding the program makes it unaccountable to U.S. citizens and to the unintended victims of the attacks.
In one drone strike reviewed by Amnesty International, the organization said it appeared that rescuers responding to a drone attack were fired on with another drone missile — something Amnesty International said could be considered a "war crime" if the second attack was intentional.
The White House said it "strongly" disagreed with the findings in the reports.
The Obama administration may face more pressure to defend the program in the coming days and weeks.
On Wednesday, Obama was set to meet with Pakistan's Prime Minister Nawaz Sharif, who has promised to bring up drone attacks in his talks with the president.
Sharif on Tuesday urged the U.S. to end drone attacks completely, saying they represented a "major irritant" in U.S.-Pakistan relations.
"I would therefore stress the need for an end to drone attacks," he said at the U.S. Institute of Peace.
He said Pakistan's political parties believed that drones violated the country's territorial integrity and interfered with its own efforts to fight extremism.
The U.N. will also present a report on drones later this week. Its report encourages the U.S. to make the program more transparent.
Next week two children who were injured by drone strikes in Pakistan plan to testify in front of Congress on the effects of the drone program at the request of Florida Rep. Alan Grayson, a Democrat.
Al Jazeera and wire services