 But in March 1945, as the Allies made further advances in Asia, the Japanese relieved French officials of their authority, rounded up all foreign nationals, and placed them under guard in concentration camps.Because of his known enthusiasm for shortwave radio, Groslier was suspected by the Japanese of being part of the anti-Japanese resistance.On June 18, 1945, in Phnom Penh, while imprisoned by the Kempeitai, Groslier died under torture.