Son, His Wife Rearrested for Allegedly Killing Father with Antifreeze Agent; 3rd Arrest of Couple Suspected of Killing Daughter, Aunt

Yomiuri Shimbun file photos
Kenichi Hosoya, left, and Shiho

A couple that is in custody for two suspected murders was rearrested on Friday on suspicion of killing the male suspect’s father by poisoning him with an antifreeze agent in Taito Ward, Tokyo, police said.

Former company executive Kenichi Hosoya, 43, and his wife Shiho, 38, were already under arrest for murdering their 4-year-old daughter and Kenichi’s sister by giving them the same liquid, making this their third arrest.

According to the Metropolitan Police Department, the two are suspected of forcing Kenichi’s father, Isamu, then 73, to ingest ethylene glycol, a chemical contained in antifreeze agents used in cars, between August 2017 and June 2018, which caused him to develop sepsis and resulted in his death on June 5, 2018. Both suspects have remained silent, but the police believe the couple sought to gain control of Isamu’s company and inheritance.

Isamu became ill around March 2017 and died about a year later after being repeatedly hospitalized. As he was believed to have died of a normal illness, no autopsy was performed.

Following the incidents involving Kenichi’s daughter and sister, an analysis was conducted on Isamu’s blood and blood test results, which remained at the hospital. The analysis showed changes that matched the characteristics observed after ethylene glycol ingestion.

Isamu ran a leather processing company in Taito Ward and a hotel in the Asakusa area. Around the time of his death, Kenichi became the president *of both companies* and Shiho became an executive, thereby taking over the management.

The MPD arrested the couple in February on suspicion of murdering their daughter Yoshiki and again in March for the murder of Kenichi’s older sister Minako Hosoya, who was 41 at the time.

In January 2018, Kenichi’s mother, Yaeko, then 68, also died in hospital. Yaeko, who was an executive at the company, had been diagnosed with chronic kidney failure during her lifetime.