 Chang wrote that there is " compelling evidence " that the Japanese themselves , at the time , believed that the death toll may have been as high as 300 @,@ 000 . She cited a message that Japan 's foreign minister Kōki Hirota relayed to his contacts in Washington , DC in the first month of the massacre on January 17 , 1938 . The message acknowledged that " not less than three hundred thousand Chinese civilians [ were ] slaughtered , many cases in cold blood . " 
