Authorities in Japan have arrested a 16-year-old girl for allegedly killing a classmate, then mutilating her. 

The Japan Times reports that the suspectwhose name has not been released because she's a minorbludgeoned 15-year-old Aiwa Matsuo with a hammer and choked her with rope before cutting off her head and hand with a saw. Matsuo's remains were discovered inside of the suspect's apartment in Sasebo on Saturday. 

Police told the Times that four posts made on the forum 2Channel triggered suspicion: 

“Oh no, blood keeps pouring out even though I have wiped it away many times,” said one of the messages posted, which carried the subject line “I have ended up killing.”

“I’ve tried to warm (the body) as it got cold, but it doesn’t warm up. . . . Everyone, (do you want to know) what color the brain is?” said another message. The user then posted a message saying: “I’ll take good care of the brain and the spinal cord, putting them in a solution.”

Furthermore, the Times said the author of the posts uploaded images depicting "a hand of what appeared to be that of the user and a cloth, both covered with blood." Though it hasn't been confirmed that the suspect made the posts, she confessed to Matsuo's murder on Sunday. She had reportedly struggled following her mother's death at the end of last year, as well as with her father's decision to remarry quickly.

The Times adds that she had been living alone since April to prepare for an abroad program.

[via The Japan Times]

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