TOKYO - What began as a missing persons case led Japanese police to the gruesome discovery of nine dismembered bodies, including two severed heads, as they arrested 27-year-old Takahiro Shiraishi on Tuesday (Oct 31).

The nine victims are said to be eight women and one man. They include a 23-year-old woman from Tokyo's Hachioji suburb whose brother filed a missing persons report last Tuesday.

The woman was said to have posted on Twitter that she had wanted to take her own life, and was looking for a companion to do so with her. That was the first contact she had with the suspect, media reports said, quoting police sources.

Police suspect the nine cases started in late August, when Shiraishi moved into his two-storey apartment in Zama city outside of Tokyo, where the body parts were found.

Shiraishi, who has not been charged, is said to have confessed to the crimes to Tokyo police.

"I dismembered the bodies in the bathroom," he was quoted by public broadcaster NHK as telling the police. "There is no doubt that I committed murder, and had the intent of destroying evidence."

After dismembering the corpses, he reportedly covered them in cat litter and hid them in cold storage boxes to mask the smell.

Two severed heads were kept chilled in an ice box at the entrance of Shiraishi's apartment, while the other body parts were found in picnic coolers.

Shiraishi, whose occupation is unknown, was tracked down based on security camera footage showing the woman walking with him near the Hachioji station, and later at the Sobudaimae station near his home last Monday.

Police are working to identify the other victims.