Corporal Griego was a member of the 17th Infantry Regiment, 7th Infantry Division. He was seriously wounded by the enemy in Korea on 27 September 1950 and died of those wounds later that day.

Griego was awarded the Purple Heart, the Combat Infantryman Badge, the Korean Service Medal, the United Nations Service Medal, the National Defense Service Medal, the Korean Presidential Unit Citation and the Republic of Korea War Service Medal.