The father of a 16-year-old Japanese schoolgirl who confessed to decapitating a classmate earlier this year has killed himself, news reports said Monday.

The 53-year-old, whose name was withheld, was found hanged in his home on Sunday in Sasebo, southwestern Japan, Jiji Press said.

His daughter was arrested late July on suspicion of murdering her 15-year-old fellow student after police discovered a dismembered body on a bed in the suspect's home.

The alleged murderer, whose name was not released as she is a minor, has confessed to decapitating the victim and cutting off her hand, police said, reportedly telling investigators she "wanted to dissect" someone.

"My daughter's act can never be forgiven for any reason or cause," her father said in a statement in August.

"When I think of the shock and sorrow felt by the bereaved family, it breaks my heart," he said. "I can't find the words for an apology."

The father of the victim said he could "never forgive the criminal who bereaved my loved daughter of her life and future."

The suspect's mother died of cancer last year, and she began living on her own after her father remarried earlier this year.

The father made his daughter undergo psychiatric treatment after she attacked him with a metal baseball bat in March.

A police spokesman in Sasebo declined to comment on the news reports.