The conflict started on July 15, when the Japanese attaché in Moscow demanded the removal of Soviet border troops from the Bezymyannaya (сопка Безымянная, Chinese name: Shachaofeng) and Zaozyornaya (сопка Заозёрная, Chinese name: Changkufeng) Hills to the west of Lake Khasan in the south of Primorye, not far from Vladivostok, claiming this territory by the Soviet–Korea border.