WASHINGTON » Two weeks ago in Pakistan, Central Intelligence Agency sharpshooters killed eight people suspected of being militants of the Taliban and al-Qaida, and wounded two others in a compound that was said to be used for terrorist training.

Then, the job in North Waziristan done, the CIA officers could head home from the agency's Langley, Va., headquarters, facing only the hazards of the area's famously snarled suburban traffic.

It was only the latest strike by the agency's covert program to kill operatives of al-Qaida, the Taliban and their allies using Hellfire missiles fired from Predator aircraft controlled from half a world away.

The White House has authorized an expansion of the CIA's drone program in Pakistan's lawless tribal area, officials said this week, to parallel the president's decision, announced Tuesday, to send 30,000 more troops to Afghanistan.

U.S officials are talking with Pakistan about the possibility of striking in Baluchistan for the first time—a controversial move since it is outside the tribal areas—because that is where Afghan Taliban leaders are believed to hide.

By increasing covert pressure on al-Qaida and its allies in Pakistan, while ground forces push back the Taliban's advances in Afghanistan, U.S. officials hope to eliminate any haven for militants in the region.

One of Washington's worst-kept secrets, the drone program is quietly hailed by counterterrorism officials as a resounding success, eliminating key terrorists and throwing their operations into disarray. But despite close cooperation from Pakistani intelligence, the program has generated public anger in Pakistan, and some counterinsurgency experts wonder whether it does more harm than good.

Assessments of the drone campaign have relied largely on sketchy reports in the Pakistani news media, and some have estimated several hundred civilian casualties. Saying that such numbers are wrong, one government official agreed to speak about the program on condition of anonymity. About 80 missile attacks from drones over almost the last two years have killed “;more than 400”; enemy fighters, the official said, offering a number lower than most estimates but in the same range. His account of collateral damage, however, was strikingly lower than many unofficial counts: “;We believe the number of civilian casualties is just over 20, and those were people who were either at the side of major terrorists or were at facilities used by terrorists.”;

That claim, which the official said reflected the Predators' ability to loiter over a target feeding video images for hours before and after a strike, is likely to come under close scrutiny from human rights advocates. Tom Parker, policy director for counterterrorism at Amnesty International, said he found the estimate “;unlikely,”; noting that reassessments of strikes in past wars had usually found civilian deaths undercounted. Parker said his group was uneasy with drone attacks anyway: “;Anything that dehumanizes the process makes it easier to pull the trigger.”;

Yet with few other tools to use against al-Qaida, the drone program has enjoyed bipartisan support in Congress and was escalated by the Obama administration in January. More CIA drone attacks have been conducted during Obama's administration than during that of President George Bush.

The political consensus in support of the drone program, its antiseptic, high-technology appeal and its secrecy have obscured just how radical it is. For the first time in history, a civilian intelligence agency is using robots to carry out a military mission, selecting people for killings in a country where the United States is not officially at war.

In the months after the Sept. 11, 2001, attacks, CIA officials were not eager to embrace killing terrorists from afar with videogame controls, said one former intelligence official. “;There was also a lot of reluctance at Langley to get into a lethal program like this,”; the official said. But officers grew comfortable with the program as they checked off their hit list more than a dozen notorious figures, including Abu Khabab al-Masri, a Qaida expert on explosives; Rashid Rauf, accused of being the planner of the 2006 trans-Atlantic airliner plot; and Baitullah Mehsud, leader of the Pakistani Taliban.

The drone warfare pioneered by the CIA in Pakistan and the Air Force in Iraq and Afghanistan is the leading edge of a wave of push-button combat that will raise legal, moral and political questions around the world, said P.W. Singer, a scholar at the Brookings Institution and author of the book “;Wired for War.”;

Forty-four countries have unmanned aircraft for surveillance, Singer said. So far only the United States and Israel have used them for strikes, but that number will grow. “;We're talking about a technology that's not going away,”; he said.

There is little doubt that “;warheads on foreheads,”; in the vernacular of intelligence officers, have been disruptive to the militants in Pakistan, removing leaders and fighters, slowing movement and sowing dissension as survivors hunt for spies who may be tipping off the Americans. Yet the drones are unpopular with many Pakistanis, who see them as a violation of their country's sovereignty—one reason the United States refuses to officially acknowledge the attacks. A poll by Gallup Pakistan last summer found only 9 percent of Pakistanis in favor of the attacks and 67 percent against, with a majority ranking the United States as a greater threat to Pakistan than its archrival, India, or the Pakistani Taliban.

Interestingly, residents of the tribal area where the drone attacks actually occur, who bitterly resent the militants' brutal rule, are far less critical of the drones, said Farhat Taj, an anthropologist with the Aryana Institute for Regional Research and Advocacy, who visits the tribal area frequently. A study of 550 professional people living in the tribal area was conducted late last year by the institute. About half of those interviewed called the drone strikes “;accurate,”; six in 10 said they damaged militant organizations, and almost as many denied they increased anti-Americanism.

Taj, who lived at the edge of the tribal area until 2002, said residents would prefer to be protected by the Pakistani army. “;But they feel powerless toward the militants and they see the drones as their liberator,”; she said.

In an interview this week with the German magazine Der Spiegel, the Pakistani prime minister, Syed Yousuf Raza Gilani, said the drone strikes “;do no good, because they boost anti-American resentment throughout the country.”;

U.S. officials say that despite such public comments, Pakistan privately supplies crucial intelligence, proposes targets and allows the Predators to take off from a base in Baluchistan.

Pakistan's public criticism of the drone attacks has muddied the legal status of the strikes, which U.S. officials say are justified as defensive measures against groups that have vowed to attack Americans. Philip Alston, the U.N. special rapporteur for extrajudicial executions and a prominent critic of the program, has said it is impossible to judge whether the program violates international law without knowing whether Pakistan permits the incursions, how targets are selected and what is done to minimize civilian casualties.

A spokesman for the CIA, Paul Gimigliano, defended the program without quite acknowledging its existence. “;While the CIA does not comment on reports of Predator operations, the tools we use in the fight against al-Qaida and its violent allies are exceptionally accurate, precise and effective,”; he said. “;Press reports suggesting that hundreds of Pakistani civilians have somehow been killed as a result of alleged or supposed U.S. activities are—to state what should be obvious under any circumstances—flat-out false.”;

Between 2004 and 2007, the CIA carried out only a handful of strikes. But pressure from the congressional intelligence committees, greater confidence in the technology and reduced resistance from Pakistan led to a sharp increase starting in the summer of 2008.

Former CIA officials say there is a rigorous protocol for identifying militants, using video from the Predators, intercepted cell phone calls and tips from Pakistani intelligence, often originating with militants' resentful neighbors. Operators at CIA headquarters can use the drones' video feed to study a militant's identity and follow fighters to training areas or weapons caches, officials say. Targeters often can see where wives and children are located in a compound or wait until fighters drive away from a house or village before they are hit.

The wife and parents-in-law of Mehsud were killed along with him, but that was an exceptional decision prompted by the rare chance to attack him, the official said.

The New America Foundation, a policy group in Washington, studied news reports and estimated that since 2006 at least 500 militants and 250 civilians had been killed in the drone strikes. A separate count, by The Long War Journal, found 885 militant deaths and 94 civilian deaths.

But the government official insisted on the accuracy of his far lower figure of approximately 20 civilian deaths, noting that the Pakistani press rarely reported local protests about civilian deaths, routine occurrences when bombs in Afghanistan have gone astray.

Daniel S. Markey, who studies South Asia at the Council on Foreign Relations, said the comments of two anti-Taliban tribal leaders he spoke with on a recent trip to Pakistan seemed to capture the paradox of the drones.

The tribal leaders told him that the strikes were taking out dangerous militants while causing few civilian deaths. But they nonetheless pleaded for a halt to the attacks. The tribal leaders said the strikes stirred up anger toward the United States and the Pakistani army, and “;made them look like puppets,”; Markey said. “;It gave the lie to the argument we've made for a long time—that this fight is theirs, too.”;