Ibaraki Family Homicide perpetrator Yoshiyuki Okaniwa was an animal abuser since childhood
| Murderer and animal abuser | |
|---|---|
|
| |
| Name | Yoshiyuki Okaniwa (岡庭由征) |
| Age | 26 (at time of indictment) |
| Occupation | Unemployed |
| Known Identifiers | |
| Status | Indicted |
| Involvement | Perpetrator of the 2019 Ibaraki family homicide. Has a long and documented history of serial animal torture, arson, and attempted murder beginning in his childhood. |
| Punitive Measure | Indicted for murder and attempted murder. Previously served a 5-year sentence in a juvenile medical reformatory. |
Yoshiyuki Okaniwa (岡庭由征) is a Japanese man indicted for the September 2019 familicide in Sakai, Ibaraki Prefecture.[1] The case is a significant example of the criminological link between animal cruelty and interpersonal violence, as Okaniwa had a long and sadistic history of torturing animals and attempting to murder strangers as a teenager, for which he was previously incarcerated.[2]
Early life and family background
Born in 1994 in Saitama Prefecture, Okaniwa was raised in an affluent family.[2] His grandfather was a local councilman, and his father ran a successful construction business, affording Okaniwa a privileged upbringing, including a credit card with no spending limit.[2]
His violent tendencies emerged in elementary school, where he began by torturing insects, birds, and snakes before escalating to cats, allegedly because his father disliked them.[2] Neighbors reported frequently finding cat carcasses near his home that had been beaten with hammers, bludgeoned, or buried alive.[2] His family was aware of his behavior but their response was dismissive, only telling him "You shouldn't do that."[2] According to one report, when a teacher confronted Okaniwa's father about the cat killings, the father responded, "Killing stray cats is protecting the environment, it's reasonable no matter how you kill them."[3]
Juvenile crimes and escalation (2010–2011)
Okaniwa's violent behavior escalated dramatically during his teenage years.
High School Incidents and Arson
In October 2010, while in high school, Okaniwa sent a classmate a link to an overseas cat torture video and then admitted to killing cats himself.[3] He began bragging to classmates about committing arson, showing them photos of fires he had set in portable toilets and on cars and motorcycles.[1]
The situation culminated in late November 2011, when he brought a cat's head in a jar to school, boasting to classmates, "I killed the cat in 5 seconds."[3] The incident caused panic among students and led to his expulsion.[2]
2011 Knife Attacks
After being expelled, Okaniwa's violence turned toward humans in two unprovoked knife attacks:
- November 18, 2011: He stabbed a **15-year-old** junior high school girl in the chin as she was walking home in Misato, Saitama.[3]
- December 1, 2011: Just two weeks later, he attacked an **8-year-old** elementary school girl in Matsudo, Chiba, stabbing her multiple times in the abdomen and causing serious injuries.[3][2]
Arrest and Juvenile Trial
Following the stabbings, the then 16-year-old Okaniwa was arrested.[3] A search of his home uncovered a collection of 71 knives.[1] During his trial in 2013, he showed no remorse, telling the court he attacked people because he wanted to kill someone, stating, "Killing is more important. That's what excites me."[1] He admitted that killing brought him pleasure and sexual gratification.[1]
Despite the prosecution arguing for a lengthy prison sentence, the defense successfully argued for rehabilitation.[1] Okaniwa was diagnosed with a pervasive developmental disorder and the presiding judge, Tamura Shin, sentenced him to five years in a medical juvenile reformatory.[1] He was released back into society in 2018.[2] The families of his victims never received an apology from him or his family.[1]
Ibaraki family homicide (2019)
- The Kobayashi family home, where the two parents were murdered and two children were severely injured:
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On the night of September 23, 2019, an intruder broke into the home of the Kobayashi family in Sakai, Ibaraki.[1] The attacker repeatedly stabbed the family members, killing the parents, **Mitsunori Kobayashi**, 48, and **Miwa Kobayashi**, 50.[1] Their son was seriously injured, and their youngest daughter sustained minor injuries.[1] Only the eldest daughter, who was sleeping in a separate room on the first floor, was unharmed.[1]
The case went cold for over a year and a half, as the attack appeared to be random, with no signs of robbery or a personal grudge.[1] Investigators eventually identified Okaniwa as the prime suspect.
2021 arrest and indictment
In May 2021, police arrested Yoshiyuki Okaniwa for the Kobayashi family murders.[1] A search of his home revealed a large number of knives, approximately 45kg of sulfur, and books on how to produce sarin nerve gas, suggesting he may have been planning a larger attack.[1] After a three-month psychiatric evaluation determined he was criminally responsible, he was formally indicted for murder and attempted murder.[4]
See also
References
- ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 1.14 (June 10, 2021). "「殺すほうが大事です。そっちのほうが、興奮するから」殺人に快楽を覚える“反社会性パーソナリティ障害”", Shukan Bunshun. Retrieved September 10, 2025from https://bunshun.jp/articles/-/46060
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 (November 15, 2021). "日本富二代虐猫成性,长大后残忍屠杀一家四口", The Paper. Retrieved September 10, 2025from https://www.thepaper.cn/newsDetail_forward_14656726
- ↑ 3.0 3.1 3.2 3.3 3.4 3.5 (November 21, 2020). "《茨城一家殺傷》岡庭容疑者(26) は10年前に「連続通り魔」を起こした“猫殺し少年”だった", Shukan Bunshun. Retrieved September 10, 2025from https://bunshun.jp/articles/-/41668
- ↑ (September 17, 2021). "境町家族4人殺傷事件殺人などの罪で起訴 水戸地検", LuckyFM Ibaraki Broadcasting. Retrieved September 10, 2025from https://lucky-ibaraki.com/news_list/66272/