A 44-year-old woman in Osaka Prefecture has been arrested on suspicion of murdering her brother in March. Police initially treated his death as a suicide, but now believe the woman spiked his drink with sleeping drugs and forged a suicide note.
Company executive Akemi Adachi was arrested Wednesday on suspicion of killing 40-year-old Masamitsu Adachi at their parents' house in Sakai on March 27, police said. She denies the charge.
Masamitsu Adachi was found lying on the floor of a bathroom where charcoal had been burned to produce carbon monoxide.
The siblings' 67-year-old mother was also found collapsed at the house that day and later told investigators she "lost consciousness after drinking a matcha latte made by Akemi," investigative sources said.
The house was also used as an office for a company run by the siblings' 67-year-old father, who has been in a vegetative state since collapsing at home in January with a condition caused by low blood sugar. The police will investigate whether Akemi was involved in her parents' ailments, the sources said.
The suspect had said prior to her arrest that she had nothing to do with Masamitsu Adachi's death, saying she would "gain nothing from his death."
A police autopsy, however, later detected traces of several sleeping drugs in his body that matched those Akemi Adachi had been prescribed by a doctor.
The sources also said the police found evidence on her computer that she had created a text purporting to be a suicide note left by her brother.
Akemi Adachi asked her brother's wife to come to the house urgently on March 27 and handed her the suicide note upon her arrival. The wife then noticed the smell of carbon monoxide and found her husband collapsed in the bathroom.
