Died as a prisoner of war.
From Find a Grave:
1st Sgt. William F. Glaab Jr. was held as a POW in the Philippine Islands. In December 1944, he was boarded onto the Oryoku Maru for transport to Japan. The ship sailed on December 13th and came under attack from American planes on December 14th. As evening approached, the attack was called off. The next day the planes returned and continued the attack. When the pilots saw the large number of men climbing from the ship's holds, they realized the ship was carrying POWs and called off the attack. After the POWs were off the ship, the attack resumed and the ship was sunk by American planes at Subic Bay, Philippine Islands, on December 15, 1944. The surviving POWs were boarded onto the Enoura Maru which sailed on December 27th and reached Takao, Formosa, by the New Year. While docked it was bombed by American planes on January 9, 1945, killing many of the POWs. The surviving POWs were boarded onto the Brazil Maru which sailed on January 13th and reached Japan on January 29, 1945. In Japan, he was sent to Fukuoka #4 where he died. ∼ From the Town of Tusten Historian obituary collection, Narrowsburg, Sullivan Co., NY: "Sgt William Glaab Jr son of M & M William Glaab who had been a prisioner of war in a Japanese prision camp since the fall of the Philippines had died at Beri beri on Feb 19 1945. His parents survive and 1 brother Arnold and 2 sisters Mrs Harry Birch and Miss Ethel Glaab."