The Yemeni president acknowledged the 2009 strike in an interview last year. The Yemeni Embassy statement Tuesday said the surviving families had been compensated. The statement said the use of drones was under review as part of the country's ongoing national dialogue between the president and Yemeni tribal factions.
In Pakistan, the U.S. considers its drone program to be a key weapon against insurgent groups that it says stages cross-border forays into neighboring Afghanistan. But the belief, widespread in Pakistan, that the strikes kill large numbers of civilians sparks resentment and complicates the two countries' ability to coordinate efforts against militants based in the country, including al-Qaida.
The U.S. drone policy sets a dangerous precedent "that other states may seek to exploit to avoid responsibility for their own unlawful killings," Amnesty said.
Amnesty's report said that the grandchildren of the woman killed told the group that missile fire struck on Oct. 24, 2012, as she was collecting vegetables in a family field in the North Waziristan tribal area, a major militant sanctuary near the Afghan border. Three of the grandchildren were wounded, as were several others who were nearby, the victims said.
An even deadlier incident noted by the Amnesty report occurred in North Waziristan on July 6, 2012. Witnesses said a volley of missiles hit a tent where a group of men had gathered for an evening meal after work, and then a second struck those who came to help the wounded, one of a number of attacks that have hit rescuers, the rights group said.
Witnesses and relatives said that 18 male laborers with no links to militant groups died, according to Amnesty. Pakistani intelligence officials at the time identified the dead as suspected militants.
"We cannot find any justification for these killings. There are genuine threats to the USA and its allies in the region, and drone strikes may be lawful in some circumstances," said Mustafa Qadri, Amnesty International's Pakistan researcher. "But it is hard to believe that a group of laborers, or an elderly woman surrounded by her grandchildren, were endangering anyone at all, let alone posing an imminent threat to the United States."