Some researchers estimate that between 40,000 and 60,000 people were killed, which corresponds to the figures from three sources; one is the Red Army's official journal of the time, Hangdibao and another is that of Miner Searle Bates of the International Safety Zone Committee, and the third is the aforementioned figure written by John Rabe in a letter. John Rabe, Chairman of the International Committee for the Nanking Safety Zone, estimated that between 50,000 and 60,000 (civilians) were killed. However, Erwin Wickert, the editor of "The diaries of John Rabe", points out that "It is likely that Rabe's estimate is too low, since he could not have had an overview of the entire municipal area during the period of the worst atrocities. Moreover, many troops of captured Chinese soldiers were led out of the city and down to the Yangtze, where they were summarily executed. But, as noted, no one actually counted the dead."