Murder of Sakurako Hagi and Kaede Hagi (Osaka child abandonment case)

On June 9, 2010, Sanae Shimomura, a 23-year-old single mother in Osaka, Japan, sealed shut the door of her apartment, leaving her 3-year-old daughter Sakurako Hagi and 1-year-old son Kaede Hagi confined inside. According to Wikipedia's account of the case, neighbors reported hearing the children crying for many weeks, but this crying eventually stopped. Residents nearby did not raise alarm, apparently assuming the children were going through a difficult developmental phase rather than suspecting they had been abandoned.

Shimomura stopped coming to work, and after several days a colleague went to check on her. The colleague noticed an unusual smell coming from beyond her sealed apartment door. When police subsequently entered the apartment, they found both children dead inside.

The case drew scrutiny of social service response, as social workers had reportedly attempted to visit the apartment multiple times during the period the children were confined, but never found anyone home to answer. The apartment itself was located in a busy, populated area of Osaka, yet no one in the vicinity realized that two young children were sealed inside and in danger.

Shimomura was arrested on July 30, 2010, roughly seven weeks after she sealed the apartment. In statements reported afterward, she said she had wanted free time for herself, and was quoted as saying she had grown "tired of feeding and bathing" her two children.

She was ultimately sentenced to 30 years in prison for the murders of her two children. As of 2025, according to Wikipedia, Shimomura remains imprisoned.

The case has been noted alongside other similar incidents of child confinement and abandonment, including a case involving two children abandoned in an apartment in Calgary, Canada, and the Sugamo child abandonment case, a comparable incident that occurred in a neighborhood near Tokyo, Japan.

This dossier is based on a single detailed secondary source (Wikipedia) describing the case's facts, arrest, and sentencing. Two contemporaneous news links (Japan Times and Mainichi Daily News) are cited by the Wikipedia article as references but were not independently accessible for this dossier's fact-drawing; they are included here as corroborating citations only.