WASHINGTON (AP) — The United States on Tuesday defended drone strikes targeting al-Qaida operatives and others it deems enemies, rejecting reports by two human-rights groups questioning the legality of strikes they asserted have killed or wounded scores of civilians in Yemen and Pakistan.

Human Rights Watch alleged that 82 people, at least 57 of them civilians, were killed by the unmanned aircraft and other aerial strikes in Yemen between September 2012 and June 2013 and called such strikes unlawful or indiscriminate. Amnesty International called on the U.S. to investigate reports in Pakistan of civilian casualties, among them a 68-year-old grandmother hit while farming with her grandchildren.