Murder of Rikako Okamoto
2005 murder in Japan
In 2005 at Hiratsuka, Kanagawa Prefecture, Japan, Rikako Okamoto (岡本 利加香, Okamoto Rikako; 1986 – c. October 12, 2005) was murdered and her mother Chizuko Okamoto (岡本 千鶴子, Okamoto Chizuko) (born July 17, 1951) was later convicted of killing her own daughter. Chizuko Okamoto was also suspected as a serial killer who might have killed at least four others, but was not charged. Asahi Shimbun described her mysterious incident as the "house of horrors".
Background
Chizuko Okamoto was born in Aomori Prefecture. She ran away from her first husband in 1975 and began a relationship with the man who would later become her common-law husband. Her first husband died in a tsunami on Okushiri Island in 1993.
Chizuko's six-year-old son, Toshihide, disappeared in 1984. She gave birth to two children in 1985 and 1987, but did not report their births. Her common-law husband died of illness in 1997.
“Murder of Rikako Okamoto” enters the record as 2005 murder in Japan. Crown Archives preserves that source wording while asking what Murder, Rikako and Okamoto can confirm, complicate or overturn.
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The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Aug 18, 2026. The linked authority identifier is Q6938031. None of the 0 selected statements returned an explicit reference. The first chronological checks are 2005, 1986, 1951 and 1975.
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This entry incorporates text from “Murder of Rikako Okamoto” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.