In this 2010 photo, an unmanned U.S. Predator drone flies over Kandahar Air Field in southern Afghanistan. (Kirsty Wigglesworth/AP)

The United States has inadvertently killed between 64 and 116 civilians in drone and other lethal air attacks against terrorism suspects in non-war zones, the Obama administration said Friday.

In releasing only aggregate figures that did not include when or where the strikes occurred, the administration shielded those claims from meaningful public scrutiny, even as it sought to bolster its own assertions about the accuracy and effectiveness of the operations.

Independent groups, whose own tracking of civilian deaths have produced far higher numbers, said they appreciated the administration’s effort. But they said it fell far short of President Obama’s repeated promises of greater transparency about his administration’s extraordinary reliance on armed drones in overseas counterterrorist operations.

The unintentional deaths, according to previously unreleased administration figures, came in a total of 473 CIA and military counterterrorism strikes between 2009 and the end of 2015. Those attacks, it said, killed between 2,372 and 2,581 “combatants” in countries where the United States is not at war.

Although it did not name the countries, they include Pakistan, Yemen, Somalia and Libya. The figures do not include deaths in ground operations, such as the one that killed Osama bin Laden and four others in Pakistan in 2011, or operations in the administration-designated war zones of Afghanistan, Iraq and Syria.

The release was accompanied by an executive order, signed by Obama, that would require future presidents — unless he or she supplanted or amended it with an order of their own — to annually release similar lists. It also says that the families of civilians killed by the United States should receive condolence payments. And it orders U.S. government agencies to consult with non-government groups and conduct regular reviews of casualty trend lines.

The order is “a very deliberate attempt to ensure that the architecture . . . is durable, sustainable and lasting well beyond the next seven months or so,” said one of four senior administration officials who jointly briefed reporters on conditions of anonymity set by the White House.

“To undo it,” the official said, “any successor administration would need to take an affirmative action,” an indication of expectations that the use of drone killings will continue under Obama’s successor. Both the executive order and the casualty statistics, this official said, are also intended to “set a positive example” for other countries using drone technology for targeted killings.

Release of the non-combatant casualty counts provoked a flood of reaction from groups who questioned the value of the numbers.

“Unless details are provided on specific incidents, it’s not possible to determine if individuals killed were civilians, and thus whether the U.S. is complying with its own policy and with international law,’ said Laura Pitter, senior U.S. national security counsel at Human Rights Watch.

In speeches in 2013 and 2016, President Obama stressed that the U.S. tries to avoid civilian deaths as a result of drone strikes – but doesn't always succeed. (The Washington Post)

The New America Foundation and the Long War Journal, which have tracked drone strikes since the George W. Bush administration, each put the number of civilians killed under the current administration at just over 200. A third group, the Bureau of Investigative Journalism, says the number is far higher, estimating that as many as 325 civilians have died in U.S. counterterrorism operations since Obama took office.

The administration’s figures were cast as a rebuke to those claims, which U.S. officials have said are often inflated by erroneous press reports, terrorist propaganda, or even efforts by Pakistan and Yemen to pass off their own military miscues as U.S. drone strikes.

Officials said the administration took non-government assessments into account, as well as reports from the International Committee of the Red Cross and others that may have more access on the ground to what the government described as “non-permissive” environments.

But the office of the Director of National Intelligence, in a statement accompanying the newly released figures, said its numbers were better because it had access to more and better information before, during and after a strike, including “video operations, human sources and assets, signals intelligence, geospatial intelligence, [and] accounts from local officials on the ground,” as well as “open source reporting.”

Officials responded somewhat testily to questions about how outsiders could judge the veracity of the data. “We didn’t have to do this in the first place,” said one. “We do believe we’re trying to go the extra mile here.”

The administration’s figures were largely drawn from post-strike analyses done by the CIA and Joint Special Operations Command, both of which have conducted drone strikes and, in the case of the military, attacks by manned aircraft. Although even critics acknowledge these entities have become more accurate in their use of armed drones but say they nevertheless have institutional incentives to undercount the number of civilians they kill.

Administration officials sharply denied allegations that they indiscriminately target “military-aged males” and then label them terrorists for counting purposes. But they acknowledged the continuing use of so-called “signature strikes,” in which they may not know the identities of those they target.

“An individual may be lawfully targeted if they are formally or functionally a member of an armed group with which we are engaged in an armed conflict,” a senior official said. Functional membership, another official said, includes the extent to which “the individual performs functions to the benefit of a particular terrorist group that are analogous to those traditionally performed” by a military organization.

But “there’s no hard and fast rule that anyone killed in a particular strike within X many feet of a known combatant is therefore a combatant.” This official and others acknowledge the possibility of mistakes, which they said accounts for the range of numbers for both civilians and militants killed.

Even with the highest standards, one official said, “you’re not always right, tragically.” The lower number of 64 civilians killed counts those conclusively determined to be non-combatants; the higher number of 116 includes those whose status remained in doubt.

Issuance of the casualty figures and executive order completes a process Obama began in May 2013, when he issued a still-secret document called the Presidential Policy Guidance, or PPG, for military actions “outside areas of active hostilities.

The guidance said that “lethal force will be used only to prevent or stop attacks against U.S. persons” when capture is not feasible, according to a public summary released at the time. Such force was to be used only when there was a “near certainty” that “the terrorist target is present” and that “non-combatants will not be injured or killed.”

The administration agreed earlier this year, as part of a court case filed by the American Civil Liberties Union, to release a redacted version of the PPG document. That release has been delayed by ongoing discussions between the court and the administration over what portions can be legitimately blacked out.

To ACLU Deputy Legal Director Jameel Jaffer, the limits on information released Friday were part of a long-standing pattern.

“While we welcome today’s disclosures, transparency about the drone campaign should not be a matter of executive grace,” he said. “The executive branch should not be able to dictate the scope of the public’s ‘right to know.’ It should not be up to executive officials alone to decide what the public knows about the killings they’ve authorized.”

Julie Tate contributed to this report.