On March 7, 1938, Robert O. Wilson, a surgeon at the university hospital in the Safety Zone administrated by the United States, wrote in a letter to his family, "a conservative estimate of people slaughtered in cold blood is somewhere about 100,000, including of course thousands of soldiers that had thrown down their arms." Here are two excerpts from his letters of 15 and 18 December 1937 to his family:The slaughter of civilians is appalling. I could go on for pages telling of cases of rape and brutality almost beyond belief. Two bayoneted corpses are the only survivors of seven street cleaners who were sitting in their headquarters when Japanese soldiers came in without warning or reason and killed five of their number and wounded the two that found their way to the hospital.