Fort Riley ? A Fort Riley soldier was killed when an explosive device detonated west of Baghdad, military officials said Tuesday.

Army Staff Sgt. Christopher E. Cutchall, 30, of McConnellsburg, Pa., was killed Monday when the explosive device went off near his vehicle, the Department of Defense said.

Cutchall was assigned to Delta Troop, 4th Cavalry, 1st Brigade, 1st Infantry Division at Fort Riley.

Cutchall joined the Army in 1991 and had been stationed at Fort Riley since May 2000. He was assigned to the unit as a scout and deployed to Iraq in early September.

Cutchall is the seventh soldier based at Fort Riley killed since the war began.