KABUL, Afghanistan — One morning recently, a teenager named Bacha Zarina was collecting firewood on her family’s small farm in eastern Afghanistan. About 30 yards away, as family members recall, two Taliban commanders stood outside a house.
A missile screamed down from the sky, killing the two men instantly. Two chunks of shrapnel flew at Bacha Zarina and lodged in her left side.
Her family raced her to the nearest hospital, a half-hour’s drive away, but she died en route, an accidental victim of the rapidly escalating U.S.-led campaign of drone strikes in Afghanistan. She was 14 or 15 years old.
The U.S. military launched 506 strikes from unmanned aircraft in Afghanistan last year, according to Pentagon data, a 72% increase from 2011 and a sign that American commanders may begin to rely more heavily on remote-controlled air power to kill Taliban insurgents as they reduce the number of troops on the ground.
Though drone strikes represented a fraction of all U.S. air attacks in Afghanistan last year, their use is on the rise even as American troops have pulled back from ground and air operations and pushed Afghan soldiers and police into the lead. In 2011, drone strikes accounted for 5% of U.S. air attacks in Afghanistan; in 2012, the figure rose to 12%.
Military spokesmen in Kabul and at the Pentagon declined to explain the increase. But officers familiar with the operation said it was due in part to the growing number of armed Reaper and Predator drones in Afghanistan and better availability of live video feeds beamed directly to troops on the ground.
The increase has coincided with a shift by the Obama administration toward a new strategy in Afghanistan that relies on a smaller military footprint to go after the Taliban and remaining Al Qaeda fighters.
The use of armed drones is likely to accelerate as most of the 66,000 U.S. troops in the country are due to withdraw by the end of 2014. The remotely piloted long-range aircraft, which kill targets with virtually no risk to American lives, carry an unmistakable attraction for military commanders.
“With fewer troops, and even with fewer manned aircraft flying overhead, it’s harder to get traditional support in combat missions,” said Joshua Foust, a Washington-based analyst who has advised the U.S. military in Afghanistan. “Drones provide a good way to do that without importing a bunch of pilots and the support infrastructure they’d need to remain based there.”
The strategy isn’t without risk: Drone strikes can kill civilians, as underscored by the Sept. 23 incident that claimed Bacha Zarina’s life.
After Marine Gen. John R. Allen, the former coalition commander, issued an order limiting airstrikes in populated areas last year, U.S. and NATO forces reduced civilian casualties in air attacks by 42% in 2012, according to United Nations figures.
But after an airstrike this month that reportedly killed 10 civilians in addition to four Taliban leaders, Afghan President Hamid Karzai banned his forces from requesting coalition airstrikes in residential areas, a decree that also would apply to drones.
Defenders of drones say they are more accurate and less prone to causing civilian casualties than manned aircraft, because they can watch a potential target longer and often use smaller munitions.
When civilians are inadvertently killed, it is sometimes because they are close to a location where an airstrike is carried out, one U.S. officer said. But there also are instances when troops on the ground mistakenly call for an airstrike against a target where only civilians are present.
The U.S. military has acknowledged multiple times that it has accidentally killed civilians in drone strikes, including in 2010 when 24 Afghans were killed in Oruzgan province after being mistaken for insurgents, based on drone camera images. They were later determined to be noncombatants.
Last year, five coalition drone strikes killed 16 civilians and injured three, according to the U.N. mission in Afghanistan, which documented just one such incident in 2011. It wasn’t immediately clear whether those were strikes from U.S. drones; Britain’s Royal Air Force also flies armed Reaper drones in Afghanistan, although the vast majority of the coalition’s unmanned aircraft belong to the U.S.
Many of the recent strikes have hit eastern Afghanistan, where Taliban insurgents retain control of many villages. In Marawara district of Kunar province, where Bacha Zarina lived, the two Taliban commanders killed in the Sept. 23 strike led a group of hard-line fighters who had banned cigarettes and shaving for men, littered the area with roadside bombs, and threatened to kill Afghans who worked for the U.S. military at an outpost an hour’s drive away, villagers said.
Bacha Zarina’s older brother Saidaa, who, like many Afghans, has just one name, said in a telephone interview that the U.S. military at first denied that the airstrike had killed a civilian, citing the accuracy of drones. After Afghan officials vouched for the family’s story, the Americans paid Bacha Zarina’s father about $2,000 in compensation.
“Do mistakes happen? Yes,” said the U.S. officer, who spoke on the condition of anonymity because he was not authorized to discuss drone operations. “But they also happen with an F-16, maybe more so.”
Cmdr. Bill Speaks, a Pentagon spokesman, said, “We have always made safeguarding civilians a top priority in all operations. These strict guidelines apply to all of our weapons platforms.”
The Obama administration has come under increasing pressure this month from Congress to disclose details and legal underpinnings for drone strikes, especially a 2011 attack that killed Anwar Awlaki, an American citizen and a leader of the group Al Qaeda in the Arabian Peninsula.
On Tuesday, Sen. Lindsey Graham (R-S.C.) said U.S. drone strikes worldwide had killed 4,700 people, the first public estimate of the death toll by a U.S. official since the attacks began early in the George W. Bush administration.
“Sometimes you hit innocent people, and I hate that, but we’re at war, and we’ve taken out some very senior members of Al Qaeda,” Graham told the Easley Rotary Club in South Carolina, according to news reports.
The increase in Afghan drone strikes also has coincided with a greater U.S. military focus in the region on deterring Iran, which has put more demands on the Navy fighters flying off two U.S. aircraft carriers in the Persian Gulf and Arabian Sea. In the past, one of the carriers had focused on air operations over Afghanistan.
The U.S. military drone strikes in Afghanistan are separate from the CIA drone campaigns against suspected Taliban and Al Qaeda targets in Pakistan and Yemen. In Afghanistan, analysts say, drones often are used to back up ground forces or for killing insurgents who are spotted trying to plant roadside bombs.
But another strike last year demonstrated that U.S. forces are also using drones for targeted killings, much as the CIA is in Pakistan and Yemen.
In late July, according to officials in the eastern province of Nuristan, a teacher and another Afghan civilian were traveling in a sport utility vehicle along a rocky road toward the Taliban-held village of Waygal. Three senior Taliban leaders and a junior operative stopped the car and demanded a ride, said Shamsuddin Aselzai, the head of the provincial council, who is from that village.
Minutes later, Aselzai said, a drone strike destroyed the SUV, killing the three Taliban leaders and the teacher, Abdul Qayum, a 48-year-old father of four. The other civilian and the junior Talib were injured but survived.
Since then, Taliban leaders in Waygal have gone almost into hiding, Aselzai said, fearful of the next drone attack.
“They are afraid, otherwise they wouldn’t hide even for a second,” Aselzai said by phone. He called Qayum’s death a tragedy and a mistake, but said the drone strikes were “very useful.”
“The Taliban are destroying our country,” he said, “and we need to take some serious steps.”
Bengali reported from Kabul and Cloud from Washington. Special correspondent Hashmat Baktash in Kabul contributed to this report.