In August 2002, the Tokyo district court ruled for the first time that Japan had engaged in biological warfare. Presiding judge Koji Iwata ruled that Unit 731, on the orders of the Imperial Japanese Army headquarters, used bacteriological weapons on Chinese civilians between 1940 and 1942, spreading diseases including plague and typhoid in the cities of Quzhou, Ningbo, and Changde. However, he rejected the victims' claims for compensation on the grounds that they had already been settled by international peace treaties.