A senior superintendent who had been detained over accusations of raping at least three women last year died in a police cell in Hiroshima in an apparent suicide, police said Sunday.

Koichi Iwamoto, 58, was found unconscious with his long johns around his neck and tied to the door of the toilet in his cell in Hiroshima Chuo Police Station at around 8:20 p.m. Saturday and pronounced dead at a hospital, the police said.

According to the police, Iwamoto left what appeared to be a suicide note.

The officer, who was on suicide watch, was indicted of raping three women whom he met through a dating app and was recently served a fresh arrest warrant for the alleged rape of two others.

During the first hearing of one of the three women at the Hiroshima District Court in January, Iwamoto's defense side pleaded not guilty, saying he went to a hotel with her but did not have sex with her.

Police allege that he blackmailed the three women by telling them he would report them to the police unless they agreed to sex, and forced them to sign documents admitting to prostitution.

On loan from the Okayama prefectural police since March of last year, Iwamoto served as a senior instructor at the police school at the Chugoku Shikoku Regional Police Bureau.

Katsutoshi Ono, who oversees the management of detention in the Hiroshima prefectural police, said, "It is regrettable that an incident like this occurred. We will have a thorough probe to prevent a recurrence."

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If you are having suicidal thoughts, help is available.

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