WASHINGTON — One American service member was killed and another wounded in eastern Afghanistan on Monday in what officials described as an apparent insider attack.

The attack is the second episode in less than two months in which an American service member was killed by an Afghan security member. The United States military, which disclosed the death in a statement on Monday, did not provide additional details.

“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,” said Gen. Scott Miller, the head of the American war effort in Afghanistan, in the statement. “Our duty now is to honor him, care for his family and continue our mission.”

The Pentagon, which said that the wounded service member is in stable condition, did not identify either service member, pending family notification.