WASHINGTON (AP) -- U.S. forces attacked a hospital in northern Afghanistan last weekend, killing at least 22 people, despite "rigorous" U.S. military procedures designed to avoid such mistakes, the top commander of U.S. and allied forces in Afghanistan said Tuesday.
Gen. John F. Campbell told a Senate committee that Afghan forces requested air support Saturday while engaged in combat with Taliban fighters in the city of Kunduz, communicating with U.S. special operations troops at the scene. Those U.S. forces were in contact with the AC-130 gunship that fired on the hospital, Campbell said.
"To be clear, the decision to provide (airstrikes) was a U.S. decision, made within the U.S. chain of command," Campbell said. "The hospital was mistakenly struck. We would never intentionally target a protected medical facility."
Appearing before the Senate Armed Services Committee, Campbell said he could not provide more details about what happened, including who may have failed to follow procedures for avoiding attacks on hospitals. He said he must await the outcome of multiple investigations.
The medical clinic that was struck was operated by the medical charity Doctors Without Borders.
Campbell had disclosed on Monday that Afghan troops requested the airstrike.
"Even though the Afghans request that support, it still has to go through a rigorous U.S. procedure to enable fires to go on the ground," Campbell said. "Fires" means weapons fire — in this case howitzer or other fire from the AC-130 gunship.
Anti-war protesters sat in the front row of Tuesday's hearing with red coloring, depicting blood, on their faces. They carried signs that read: "Healthcare not warfare," ''Afghan hospital bombing is a war crime" and "Kunduz victims: RIP."
Christopher Stokes, general director of Doctors Without Borders, has said "there can be no justification for this horrible attack" and that it was critical to conduct "a full transparent independent investigation."
Campbell also testified that he has provided his superiors with options for altering President Barack Obama's plan for reducing the U.S. troop presence after 2016 from its current level of about 9,800 to an embassy-based security operation of about 1,000. He said conditions in Afghanistan have changed significantly since Obama approved that plan in 2014.
Defense Secretary Ash Carter said Monday the Pentagon is providing options to the White House and Obama will be making decisions about future force levels later this fall.
Kunduz has been the scene of heavy fighting in recent days.
A Taliban assault on Kunduz took Afghan authorities by surprise and embarrassed President Ashraf Ghani's administration. The Taliban, who attacked on multiple fronts, held the city for three days before a government counter-offensive began. Afghan forces have retaken Kunduz, an important city on the Tajikistan border, a hub for drug and gun smuggling to and from Central Asian countries.