WARNING: GRAPHIC CONTENT - Loner Tsutomu Miyazaki murdered four young girls, all aged seven and under, but blamed his horrific actions on an alter-ego called 'the Rat Man'

One of Japan's most brutal and twisted serial killers slaughtered, sexually assaulted and dismembered young children in a case that shocked the country.

Tsutomu Miyazaki - dubbed the 'Otaku Murderer' - was behind the killings of four girls in 1988 during a series of sickening attacks. The anime and porn-obsessed man engaged in necrophilia and cannibalism and showed no remorse for his appalling offences.

Miyazaki's early years in Tokyo were marked by extreme trauma. It was rumoured that he was born from an incestuous relationship between his dad and eldest sister, resulting in malformed hands that made him a constant target of ridicule.

In one instance, he was discovered peeping at his sister while she bathed, and when she and his mother challenged him, he savagely attacked both women.

His killing spree commenced when he was 26, not long after his beloved grandfather died. Experts believe this traumatic event finally sent him over the edge.

Following his grandfather's funeral, Miyazaki ate some of his ashes in order to feel closer to him, while distancing himself from his family.

His first victim was Mari Konno, a four-year-old whom he kidnapped in his car before driving her to the outskirts of Tokyo. Once there, he strangled her and then sexually abused her lifeless body.

After photographing Mari's remains, he stripped her naked and brought her clothes home as a twisted memento of his deeds. Two days later, he returned to the crime scene to sever her limbs.

As if that wasn't enough, depraved Miyazaki sent a parcel to the little girl's frantic parents - a container with her ashes, her teeth, a photo of the outfit she went missing in and a note that read: “Mari. Cremated. Bones. Investigate. Prove."

Shortly afterwards, he abducted seven-year-old Masami Yoshizawa to the same location, where he carried out his twisted ceremony once more and discarded her remains just metres from Mari. In December of 1988, he struck yet again, snatching young Erika Namba and dragging her to a car park.

He photographed her naked before murdering her and displaying her corpse at the public site. But it was his fourth and final killing that was arguably the most disturbing and brutal.

After persuading five-year-old Ayako Nomoto to allow him to photograph her, he murdered her and transported her body to his apartment where he sexually violated it over two days. He then dismembered her remains, hiding her torso in a cemetery and her head amongst the hills. He kept her hands and later ate them.

Miyazaki's campaign of terror was ultimately brought to an end in 1989 when he was confronted by the dad of a young girl whom he was photographing in the nude.

Officers detained the killer and raided his residence, discovering photographs and approximately 6,000 videos, many containing footage of his victims.

He told authorities upon his arrest: “I felt all alone. And whenever I saw a little girl playing on her own, it was almost like seeing myself.” Throughout his trial, Miyazaki refused to accept any culpability for his deeds, which he described as 'acts of benevolence'.

Instead, he attempted to claim his alter ego 'the Rat Man' had compelled him to slaughter the girls and tried to plead insanity. The plea was rejected and on June 17, 2008, he was executed by hanging for his horrific offences, aged 45.