The Interior Ministry said the car bomb in southern Zabul province also wounded 66 people. The Taliban said in a statement it was targeting an intelligence headquarters near the hospital.
The U.S. airstrike was conducted in Nangahar province early Thursday and was targeting Islamic State group fighters, according to Col. William Leggett, a U.S. military spokesman in Kabul.
Leggett said that the strike is under investigation and that U.S. forces are working with local officials to “determine whether there was collateral damage.”
“We are fighting in a complex environment against those who intentionally kill and hide behind civilians,” Leggett said in a statement.
Attaullah Khogyani, the spokesman for the Nangahar provincial governor, said that the strike hit farmers working in fields and that the death toll is expected to rise. But later in the day, Gov. Shahmahmood Miakhel disputed the reports of civilian casualties. He said all those killed were militants.
The Islamic State has significantly fewer forces than the Taliban, and in many parts of the country they fight each other, but U.S. officials see the Islamic State as the greater terrorist threat.
Many in Afghanistan feared new waves of violence after the collapse in peace talks this month, coupled with preparations for presidential elections Sept. 28.
Both U.S. and Taliban forces pledged to step up attacks after President Trump abruptly declared the talks “dead” after more than a year of negotiations. The Taliban also have repeatedly pledged to derail a vote they described as a “fake presidential election,” warning civilians to stay away from election-related offices and events.
If violence escalates, many fear extremely low turnout that could undermine the election’s legitimacy. Security concerns have delayed the election twice, and the government announced that some 2,500 out of 7,400 polling stations will be closed on election day. Most of the closed sites are in provinces where insurgents are active. The Taliban is estimated to control or influence nearly half of Afghanistan’s 400 districts, most of them rural.
In a statement condemning the violence Wednesday, Secretary of State Mike Pompeo called on the Taliban to “demonstrate a genuine commitment to peace rather than continue the violence and destruction that causes such inordinate harm to the Afghan people and the future of their country.”
Separately, Pompeo announced in a statement Thursday that the U.S. government was taking steps in response to corruption in Afghanistan. Pompeo said the United States would withdraw approximately $100 million from a large energy infrastructure project but continue to support the project by other means.
“We expect the Afghan government to demonstrate a clear commitment to fight corruption, to serve the Afghan people, and to maintain their trust,” Pompeo said. He also added that the United States would withhold $60 million due to transparency concerns regarding the Afghan national procurement authority and cease funding the Afghan monitoring and evaluation committee at the end of the year.
Sayed Salahuddin contributed to this report.