A series of operations by U.S. forces in eastern Afghanistan targeted an al-Qaida leader and a bomb-making cell, killing 19 militants, the coalition said Saturday.
An Afghan police chief said officials were checking unconfirmed reports that civilians may have been killed.
The operations took place Friday in Nangarhar and Khost provinces, volatile regions along the Pakistan border.
In the deadliest operation, the coalition said it killed 10 militants during a strike against a bomb-making cell under the command of Jalaluddin Haqqani, a fierce militant leader believed to operate out of Pakistan.
Wazir Pacha, the spokesman for Khost's provincial police chief, said a delegation of police had been sent to investigate following unconfirmed reports of civilian deaths.
The governor of Khost, Arsallah Jamal, said he did not believe any civilians had been killed but that officials wanted to make sure. He said it was unlikely that civilians would have been in the region where the operation took place.
Lt. Comm. Walter Matthews, a U.S. military spokesman, said his office had not received any reports of injuries or deaths to civilians.
"We go well out of our way to plan those operations and we do whatever we can to make sure we don't harm any civilians," he said.
Civilian deaths have long been a problem in Afghanistan for U.S. and NATO forces, and President Hamid Karzai has repeatedly pleaded with international troops to avoid such killings, which undermine support for the government and turn Afghans against the U.S. and NATO.
In a separate operation in Nangarhar, the coalition said it targeted a known al-Qaida leader believed to help move foreign fighters and weapons into Kunar province. The coalition said armed militants engaged the force with gunfire. Coalition troops returned fire and killed five militants, including an armed female.
Afghanistan is suffering through one of the most violent years since the 2001 U.S.-led invasion that ousted the Taliban's hard-line Islamist regime for sheltering al-Qaida's terrorist organization.
More than 5,300 people have died in insurgency related violence this year, according to an Associated Press count of figures from Western and Afghan officials.
