Two sisters in their 80s and the 60-year-old daughter of one of them were found dead in their home in Higashine, Yamagata Prefecture, in a suspected case of suicide, police officials said.
The bodies of Masako Hongo, 89, Chizuru Shikama, 88, and Hongo's daughter, Ritsuko, were found inside the house Tuesday by a relative who lives nearby.
The sisters were in two beds and the daughter was found hanged in the living room, the police said.
The police said they suspect suicide because the bodies had no conspicuous wounds and there were no signs of forced entry. No suicide note was found and the cause of death had yet to be determined.
The sisters were bedridden and suffering from dementia, a neighbor said. The daughter was taking care of them.