For extraordinary heroism as Commanding Officer of an Anti-Tank Company of the First Marines, First Marine Division (Reinforced), in action against enemy aggressor forces en route to Hamhung, Korea, on 10 December 1950. When a strong, well-organized hostile force ambushed the regimental motor convoy at Sudong-ni, Captain Petro immediately assumed command and, building up fire power with additional machine guns, organized the effective defense of the convoy. Repeatedly braving heavy, accurate enemy small-arms fire, he deployed his men in strategic locations and, undeterred by the difficulty of spotting the well-concealed hostile positions in the darkness, personally directed damaging fire which routed the enemy. At the height of the action, he advanced alone to rescue a severely wounded Marine and subsequently led a patrol in front of the lines to evacuate two casualties and personally captured a prisoner of war. His quick initiative, tactical ability and cool leadership during a serious crisis were contributing factors in the successful repulse of the enemy and in the continued safe passage of the convoy, thereby reflecting the highest credit upon Captain Petro and the United States Naval Service.

LTC. Petro resided in California and had been a member of the Legion of Valor since 1981.