KABUL, Afghanistan, July 6 (UPI) -- Afghan President Hamid Karzai has ordered an investigation into allegations that 15 civilians were killed in a U.S. military strike against militants.

Among the civilians reportedly killed in Friday's U.S. helicopter attack against militants along the border between Konar and Nurestan provinces were five members of one family -- a doctor and at least two children, CNN reported Sunday.

Authorities were also investigating civilian deaths from a coalition bombing in eastern Afghanistan Sunday that killed at least 23 people and wounded 10 others who were walking to a wedding party.

"The wedding party was supposed to be going from one village to another to take the bride to the house of the groom," said Hamisha Gul, district governor of Deh Bala district of Nangarhar Province.

"You will have to ask the Americans whether these were terrorists. So far as I know they were men, women and children traveling to a wedding," he said.

CNN said Karzai has faced mounting pressure to urge the United States and other nations to take more precautions when carrying out military operations against the Taliban in Afghanistan.