Japanese police arrest a leading mob figure, Tadashi Irie, third-in-command of the Yamaguchi-gumi.
- Iccho Ito, the mayor of Nagasaki, Japan, is shot at least twice outside his re-election campaign headquarters. The assassin, Tetsuya Shiroo, is alleged to be a senior member of a local gang affiliated to the Yamaguchi-gumi crime syndicate.
- Japan's third-biggest steelmaker, Kobe Steel, admits to falsification of product data. About four percent of the aluminum and copper products that it shipped from September 2016 to August 2017 were falsely labeled as meeting the specifications requested by 200 customers, including Toyota Motor Corp, Central Japan Railway Company, Mitsubishi Heavy Industries, Mazda Motor Corp, and Subaru Corp.
- The Nobel Committee awards Japanese-born British novelist Kazuo Ishiguro the Nobel Prize in Literature for his "novels of great emotional force, has uncovered the abyss beneath our illusory sense of connection with the world."
- Aquatic species from Japan hitched a ride on debris from the 2011 Tohoku earthquake and tsunami and were able to reach the West Coast of the United States alive.
- Japanese Prime Minister Shinzo Abe is expected to dissolve the House of Representatives on September 28, 2017 to make way for fresh elections.