Photo/IllutrationAkemi Adachi is driven by police to the Osaka prosecutors office on June 21. (Satoru Ogawa)

  • Photo/Illustraion
  • Photo/Illustraion

SAKAI, Osaka Prefecture--Police suspect a woman killed her brother in a staged suicide here, and are also looking into whether she caused her father's coma and brain death by injecting him with an overdose of insulin.

Osaka prefectural police cited growing evidence that 44-year-old Akemi Adachi, who is under arrest, engineered her brother's death.

They referred the case to prosecutors on June 21.

Adachi is president of Daiichi Suidokai, a plumbing business in the city's Naka Ward that was founded by her father.

Her brother, Masamitsu Adachi, who is 40 and heads a construction company, was found dead from carbon monoxide poisoning in a toilet at a building that doubled as the office of her company and home of the siblings' parents.

It was initially thought he had taken his life, but suspicions of foul play quickly emerged.

Police suspect the sister gave her brother a beverage laced with sleeping medicine on March 27 and dumped him in a sealed toilet in the living quarters of the building with a lit charcoal burner after he passed out.

She has denied killing her brother.

The brother had told his wife, 37, he was going to visit his sister’s office that day, according to police.

When Adachi contacted Masamitsu’s wife to say he disappeared after he showed up, she rushed over and discovered her husband slumped unconscious in a toilet and her mother-in-law collapsed in a separate room. Her mother survived.

The toilet had been made airtight with adhesive material sealing the gap under the door, according to investigative sources.

But investigators' suspicions were aroused because no lighter or matches were found inside the enclosed space. They also discovered a container with the same adhesive material in another room.

A postmortem turned up traces of sleeping medication in Masamitsu’s body. The same medication was found during a police search of Adachi’s home.

The mother was quoted as telling police that she “lost consciousness after drinking green tea au lait" that Adachi had prepared for her on the day her son was found dead.

There were other clues that led police to suspect that Adachi had disguised her brother's death as a suicide, according to the sources.

Immediately after Masamitsu’s death, Adachi told her sister-in-law that she found his "will" in her company's office and handed it to her.

The wife became immediately suspicious of the content and reported the matter to police.

The document contained a reference that Masamitsu was jealous because their father had shouldered Adachi’s housing loan.

But the mother, 67, told police that Masamitsu was not privy to such an arrangement, according to the sources.

At some point during the apparent family feud, a car belonging to Masamitsu’s family was vandalized with spray paint.

An analysis of Adachi’s confiscated personal computer and printer in May showed traces that the "will" was written on her computer and printed out by her printer.

It also emerged that Masamitsu was somewhere else at the time the computer logged the record.

The sources also said that Masamitsu had planned a family trip for a later date and booked accommodation at a resort hotel, another indication that things were not as they appeared to be.

A man who had known Masamitsu for 20 years said he did not notice anything unusual about his friend when they spoke by phone on the day he was found dead.

The man told The Asahi Shimbun in an interview that Masamitsu was looking forward to the family vacation.

“He treasured his family,” the man said. “I could not believe he committed suicide and thought he must have ended up being dragged into something.”

Police are also investigating the circumstances in which Adachi’s 67-year-old father was found in a coma in January from an overdose of insulin to treat his diabetes.

Masamitsu’s "will" contained a passage that basically "admitted" he injected the overdose.