 A group of ethnic Koreans (who were regarded at the time as subjects of the Japanese Empire) subleased a large tract of land from a local Chinese broker and prepared to irrigate by digging a ditch several kilometers long, extending from the Itung River across a tract of land not included in their lease and occupied by local Chinese farmers.After a considerable length of the ditch had been dug, the Chinese farmers protested to the Wanpaoshan local authorities, who dispatched police and ordered the Koreans to cease construction at once and leave the area.The Imperial Japanese Consul based at Changchun responded by sending Japanese consular police to protect the Koreans, and both Japanese and Chinese authorities in Changchun agreed to a joint investigation.