FORT CAMPBELL, Ky. (AP) _ A soldier shot and killed two sergeants after returning from a field exercise, then fatally shot himself, the Army said Wednesday.

Spec. Gregory Radcliff, 25, of Chicago was upset with his sergeant over something that happened during the military maneuvers at Fort Campbell and asked to see him in his office Tuesday, the Nashville (Tenn.) Banner reported.

He poked a pistol into the sergeant's face and fired, killing him, said the newspaper, citing an anonymous source close to the investigation. Radcliff then killed another soldier who heard the shot and had come to investigate, and shot himself before he could be stopped, it said.

Killed were 1st Sgt. George Brewster, 39, of Pinson, Ala., and Staff Sgt. Elijah Miller, 34, of Rembert, S.C. It was unclear which one was Radcliff's sergeant.

A Fort Campbell spokesman, Maj. Ed Gribbins, said the .357-caliber Magnum used was privately owned, not military issue.

Army officials said they had not established a motive for the shootings. Operation Mega Gold, a field exercise involving 3,300 soldiers, is in its second week at Fort Campbell.