KABUL, Afghanistan — A United States airstrike appeared to have badly damaged a hospital run by Doctors Without Borders in the Afghan city of Kunduz early Saturday, killing at least nine hospital staff members and wounding dozens, including patients and staff. The United States military, in a statement, confirmed the 2:15 a.m. airstrike, saying that it had been targeting individuals “who were threatening the force” and that “there may have been collateral damage to a nearby medical facility.” Accounts differed as to whether there had been fighting around the hospital that might have precipitated the strike. Two hospital employees, an...