This is a list of documented major crimes in Japan.
Date Name Deaths Location Summary 1923–1924 Satarō Fukiage 7 Kantō and Chūbu Fukiage raped and murdered six girls. He also raped and murdered a girl in 1906. Exact victim estimates are unknown but one theory puts the number at 93 while another put it at more than 100. Fukiage was executed in 1926. 1925 Aoyama-kai / Mitani-kumi gang war 3+ near Yokohama In one of the largest battles between Yakuza groups, members of the Aoyama-kai and around thirty gangs led by the Mitani-kumi are involved in a dispute over a construction contract for Tokyo Denryoku Construction in Kanagawa. Aoyama-kai is a subcontractor of Shimizu-gumi and Shimizu-gumi is losing trust due to Hazama-gumi's obstruction, which they regard as Mitani-kumi's interference. After six hours of fighting, reportedly between 600 and 2,000 gangsters are involved with weapons including rifles, pistols, swords and farm implements. The Tokyo police and the Kempei-Tai were called in after the Kawasaki police became unable to handle the situation and, although Japanese officials declared martial law, fighting did not end until a cannon was brought in by the Aoyama-gumi. The battle injured over 150 people and killed at least three. 1936 Sada Abe 1 Tokyo Sada Abe and Kichizo Ishida (her lover) engaged in erotic asphyxiation resulting in his death. When he died she then cut off his penis and testicles and carried them around with her in a handbag. Because her way of killing him was erotic, her crime gave inspiration to Japanese films, such as Nagisa Oshima's In the Realm of the Senses. 1938 Tsuyama massacre 31 rural hamlets near Tsuyama, Okayama After cutting off electricity to his village, 21-year-old Mutsuo Toi proceeded to go on a late-night killing spree with a shotgun, a katana, and an axe before killing himself. 1941–1942 Hamamatsu serial murders 9–11 near Hamamatsu, Shizuoka A deaf boy, Seisaku Nakamura murdered people in Shizuoka. He attempted to rape women and murder his family. He was arrested for nine murders in 1942. He admitted two other murders. He was sentenced to death. 1946–1948 Kotobuki San'in incident 5–84 Tokyo Miyuki Ishikawa, midwife and director of maternity home, fatally neglected 85 babies, along with several accomplices. 1945–1946 Yoshio Kodaira 7–10 Tokyo, Tochigi Former soldier Yoshio Kodaira raped and murdered ten women. In China, he admitted that he committed numerous war crimes. He also killed his father-in-law in 1932. Kodaira was executed in 1949. 1948 Teigin Bank robbery 12 Shiina, Toshima, Tokyo Sixteen people, employees of a branch of Imperial Bank (Teikoku Ginkō, aka Teigin) and their family, are poisoned by cyanide after taking chemicals given to them by a man claiming to be from the health authorities who claimed they were medication to control a nearby dysentery outbreak. The man then stole 160,000 yen before making his escape. Twelve people died. Sadamichi Hirasawa, a painter, was arrested several months later. Although sentenced to death, there were strong suspicions that he was wrongfully convicted, and successive Justice Ministers refused to sign his death warrant, resulting in a stay of execution. During his 33-year imprisonment he wrote his autobiography and died of natural causes in 1987.