A U.S. service member was killed in an apparent "insider attack" in eastern Afghanistan on Monday, military officials said.
Another American service member was wounded in the attack, according to a statement from Resolute Support, the NATO-led mission that trains and advises Afghan forces. That wounded service member is stable, officials said.
"The sacrifice of our service member, who volunteered for a mission to Afghanistan to protect his country, is a tragic loss for all who knew and all who will now never know him," Resolute Support and U.S. Forces-Afghanistan Commanding General Scott Millersaid in a statement. "Our duty now is to honor him, care for his family and continue our mission."
No further details were immediately released. Officials said that the U.S. service member who was killed was the sixth American killed in Afghanistan in 2018.
In July, another U.S. service member, Cpl. Joseph Maciel of South Gate, California, was killed and two others were wounded in what officials described as an apparent insider attack.
A member of the Afghan security forces carried out that attack at Tarinkot Airport in the southern province of Uruzgan, according to the Taliban, which did not claim responsibility.
There have also been insider attacks against Afghan forces. A Pentagon report in June said there were 47 so-called "green-on-green" attacks, or incidents where Afghan soldiers turned on their own side, in 2018.
The report said that insider attacks against Afghan national defense and security forces increased by 50 percent from the same period last year.