The U.S. military said one Afghan security force member also was killed and several were wounded in Thursday's incident. It was the second U.S. military death in Afghanistan in less than one week. On Saturday, Army Cpl. Joseph Maciel, of South Gate, California, was killed by what the U.S. is investigating as a possible attack by a member of the Afghan military.
Thursday's death marked the fourth American servicemember to be killed in Afghanistan this year. On Jan. 1, Army Sgt. 1st Class Mihail Golin, 34, of Fort Lee, N.J., was killed in fighting in Nangarhar province, and on April 30, Army Spc. Gabriel D. Conde, 22, of Loveland, Colorado, was killed in Kapisa province.
The U.S. has about 15,000 troops in Afghanistan.