NAGOYA – A female 19-year-old student who admitted killing an elderly woman and poisoning a male high school classmate appeared to show no discomfort over what she did, allowing the woman’s body to remain in her apartment for weeks as it decomposed.
The Aichi Prefectural Police said Monday the Nagoya University student appeared to have made no effort to cover up the killing of the 77-year-old woman, a member of a religious group whom she had befriended.
The day after the slaying, she took an overnight bus from Nagoya to Miyagi Prefecture to stay with her parents, the police said.
They said the teen left Tomoko Mori’s body in the bathroom of her Nagoya apartment as it decomposed and did not try to seal the door frame to prevent the foul stench pervading the unit.
The student appeared to have left clues of her state of mind on Twitter, using an account that the police have confirmed was hers. The user’s profile declared that she expected to “go to jail” after graduating from university, followed by “detention center.”
She posted numerous messages expressing sympathy for the culprits in prominent murder cases and declared that she, too, wanted to kill.
Among the accounts she followed were those related to homicides such as the Akihabara, Tokyo, stabbing spree in June 2008 and the Aum Shinrikyo cult’s deadly gas attack on the Tokyo subway system in 1995.
She posted Twitter messages almost daily since last April, but her activity decreased sharply after the chilling message “I finally did it” appeared on Dec. 7.
Mori is believed to have died that day at around noon. She disappeared after attending a regular gathering of her religious group but was seen with the student at the meeting.
The teenager is believed to have invited Mori to her apartment, where she allegedly bludgeoned the woman with a hatchet and then strangled her to death.
Police entered the suspect’s apartment on Jan. 27, about six weeks later, where they found the woman’s corpse decomposing in the bathroom.
They said the doorway had not been sealed and there was no sign that the student had used air fresheners to try to neutralize the stench.
The shoes Mori had been wearing that day were still at the door and her handbag containing a cellphone and wallet remained untouched in the living room, according to the police.
They also said they seized chemical substances from the apartment that may have been used in the earlier poisoning of a former high school classmate. The 19-year-old has allegedly admitted to the act.
The police said evidence from the 2012 case, in which a male student suddenly fell ill and reported a loss of vision, suggested poisoning by thallium, a chemical used in rodent bait.
They are investigating whether thallium was among the substances seized from the apartment.
There was, however, a clue on the Twitter account that she had obtained the poison.
“Bought thallium sulfate,” it read. “Isn’t 1 gram of thallium sulfate the median lethal dose?”