[1] Together with three female employees, he fatally poisoned two men and attempted to kill a third at his establishment in Honjō between 1995 and 1999, all as part of an insurance fraud scheme.
[3] At this establishment, he employed many young women, including his childhood friend Mayumi Take, who accepted his job offer after failing her high school entrance exam.
[4] In June 1995, 45-year-old Shuichi Sato, a steel factory worker, resorted to drinking large quantities of alcohol to help with his sleep deprivation and to avoid overwork death.
Unbeknownst to Sato, his favorite food (consisting of manjū and dorayaki) was laced with small doses of monkshood over an extended period of time by Kawamura.
[4] A day later, 47-year-old Fujimi Kawamura, a former painter who had developed a drug addiction, suddenly fell ill.[6] He was hospitalized after complaining of his poor health and survived, but feeling that he had been intentionally poisoned, the man rushed to the nearest nurse to voice his suspicions.
[3] The case quickly garnered the attention of the public and media alike, as the mass poisonings carried out by Masumi Hayashi had occurred just the previous year.
In said conferences, Yagi insisted that he was innocent, but also did a variety of other things such as chat with reporters, sing karaoke, mess around on a kickboard or show off his marksmanship skills.
In that case, the woman died of acute liver failure after taking some cold medicine and alcohol that had been laced with 4.8 grams of monkshood.