Suspect tried to cover up dismemberment of sister's body

The 21-year-old cram school student arrested on suspicion of dismembering the corpse of his sister at their home in Tokyo's Shibuya Ward appears to have tried to cover up his deeds by wiping off bloodstains from the crime site, police sources said Friday.

Traces of bloodstains, having been wiped off in his room and on the hallway walls in the three-story house, indicate that Yuki Muto killed his 20-year-old sister Azumi in his room and dragged her body into the bathroom for dismemberment, the sources said.

Severed into more than 10 pieces, the victim's head, limbs and other body parts were found packed in four plastic bags in a closet and cabinet in Muto's room on the third floor on Wednesday.

Having placed an empty aquarium on top of the cabinet, Muto was quoted as telling his father that there could be a bad smell because a shark he had been given by a friend had died.

The saw and kitchen knife, believed to have been used for the dismemberment, were family utensils and were apparently placed back to his room and kitchen with the bloodstains wiped off after the crime, according to the sources.

Azumi's head had bruises that indicate she had been hit with a blunt instrument or had hit her head as she fell over, the sources said, adding that Muto has admitted to using force in handling her.

After being arrested Thursday, Muto confessed to killing her, according to the Metropolitan Police Department.

Both were living with their dentist parents and a 23-year-old brother in the building housing a dental clinic on the first floor and a residential space on the second and third floors.

Police have yet to ascertain how many days the victim had been dead, but believe her body was dismembered last Saturday.

The mother has told the police she spoke with her daughter Saturday afternoon through the intercom at the front entrance of their house.

The mother then left for a trip with her elder son on Saturday afternoon and the father left home Sunday night to join them. The three returned home Tuesday night.

Muto was also quoted by the sources as telling his father that he did not know where Azumi was when asked where she was.

Muto was quoted by the police as saying he killed his sister because she had accused him of "having no ambition."

Azumi lived in the three-story house with her dentist father Mamoru Muto, 62, her mother, 57, who is also a dentist, and two brothers — a university student aged 23 and the suspect.

The younger brother left home Sunday afternoon for Kanagawa Prefecture to take part in a cram school program for those planning to enter medical school slated to last through Jan 11, according to the police and other sources familiar with the case.

The mother and the elder brother left for a trip together Saturday afternoon and the father left home Sunday night to join them, according to the police. The three returned home Tuesday night.