Citation... For extraordinary heroism and conspicuous gallantry above and beyond the call of duty while serving with the 3d Marines, 3d Marine Division, in action against enemy Japanese forces during the battle at the Koromokina River, Bougainville Islands, Solomon Islands, on 7 November 1943. Although several of his men were struck by enemy bullets as he led his squad through dense jungle undergrowth in the face of severe hostile machinegun fire, Sgt. Thomas and his group fearlessly pressed forward into the center of the Japanese position and destroyed the crews of 2 machineguns by accurate rifle fire and grenades.

Discovering a third gun more difficult to approach, he carefully placed his men closely around him in strategic positions from which they were to charge after he had thrown a grenade into the emplacement. When the grenade struck vines and fell back into the midst of the group, Sgt. Thomas deliberately flung himself upon it to smother the explosion, valiantly sacrificing his life for his comrades. Inspired by his selfless action, his men unhesitatingly charged the enemy machinegun and, with fierce determination, killed the crew and several other nearby-defenders. The splendid initiative and extremely heroic conduct of Sgt. Thomas in carrying out his prompt decision with full knowledge of his fate reflect great credit upon himself and the U.S. Naval Service. He gallantly gave his life for his country.