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  • Writer's pictureJohn Wick

The Peculiar Setagaya Murders

In December of 2000, a family was entirely murdered inside their home address in Western Tokyo. Even though leaving numerous clues behind at the crime scene, the killer of the family has never been identified, with the police investigation continuing even to this day. In this post, we take a look at the peculiar Setagaya Murders.

The Officer's Investigation

Staring at the crime scene photos which had been laid out on the desk of his dimly lit office, Takeshi Tsuchida fell consumed by an overwhelming sense of frustration. It'd just been over a week since the elderly lady had discovered the bodies of her family, brutally slaughtered in their own home and the police investigation thus far still had yet to identify a suspect for the crime. As chief officer of the Seijo Police station, Tsuchida had inevitably been entrusted with this high-profile case, along with orders to bring the matter to a quick resolution.

And at first glance, that had seemed a foregone conclusion, with personal belongings and forensic evidence left behind by the offender yielding vital clues, which should have irrefutably3 uncovered the Killer's identity. But within a short space of time, it had become apparent that the DNA which had been recovered from the crime scene did not relate to any held in the national database, effectively curtailing what should have been the most obvious and effective line of inquiry.

In the absence of this, his investigators had quite naturally fallen back on witness and surveillance evidence, only to come to the realization that there was frustratingly little to go on. The killer had not been captured on any of the CCTV cameras which surrounded the premises, and what little witness testimony had been uncovered thus far had proven sorely lacking in any useful detail.

Gathering the photographs together and returning them to the case file, he glanced across at the sheet of A4 paper he'd intended to use to map out the next stages of the investigation. Apart from going further afield beyond Japan's borders to inquire if the DNA evidence matched any records held in neighboring countries, the page remained dauntingly empty. A career investigator, Tsuchida had encountered few cases during his service which had affected him as much as this, given the sheer brutality and horror the attending officers had documented at the scene.

And despite their best efforts to keep the specific details of the murders from escaping into the public domain, the department's reputation was already under sustained attack. Whilst updating his superiors on the progress of the case, he had noted the concerned glances and weary sighs his remarks had elicited. He'd also been asked to comment on several newspaper articles, accusing his men of incompetency and inefficiency, citing largely historical issues with in the Tokyo Metropolitan Police, which had long since been resolved.

Taking up his pen, he stared again at the empty page before him, silently determined that he would find and punish this brutal killer. No matter what the cost or personal sacrifice, no barrier would stand in his way as he worked to identify the man who had savagely robbed four innocent family members of their lives.

It did not take long for the investigators assigned to the Setagaya killings to piece together a timeline regarding the final hours of the victims, who had spent the 30th of December like so many other families in Tokyo that day, preparing to see out the end of the year together. During the course of their day, they had gone out shopping before returning home and making arrangements for the following day's celebrations with relatives over the phone. After dinner, they had spent the evening watching television, before finally retiring to bed.

The Murders

The head of the household, 44 year-old Mikio Miyazawa works for a marketing company and had periodically logged on to his computer throughout the course of the day to check for and reply to work-related emails. Whilst he did this, his wife Yasuko had entertained their two children, eight-year-old Niina and her little brother Rei. But as the four of them had later been sound asleep in their beds, at approximately 11:30 p.m., a dark figure had slowly emerged from the interior of the park which bordered the rear of their home. This shadowy form had silently slipped from a group of trees, before cautiously scaling another tree, which stood in the garden at the address. He had then reached across and removed a protective screen which covered the second floor bathroom window, before hauling himself in through the now insecure opening.

Once inside, the offender had walked into the nearest bedroom, where six-year-old Rei was asleep, before strangling the boy to death with his bare hands. This horrendous act must have caused some level of disturbance as it immediately brought Mikio running upstairs from the first floor, where he had been sleeping. The struggle that took place between Mikio and his assailant was short and brutal. The intruder was armed with a traditional Japanese kitchen knife, which he used to repeatedly stab the father of two in the head, so hard that the end of the blade broke off, lodging itself deep inside the victim's skull.

Before he died, Mikio had successfully managed to inflict some minor injuries on his attacker, but he simply could not survive the strength and brutality of the onslaught he had faced. As his lifeless body fell backwards down the stairs into a heap, the killer then followed it down to the first floor landing, where he repeatedly hacked and slashed at it with the broken knife. After concluding this senseless desecration, he then turned and walked back up to the second floor. Here, he attacked Yasuko and her daughter, inflicting injuries far more savage than those he had inflicted upon the male members of the household, before finally ending their lives using a Santuko knife from the Miyazawa kitchen.

His goal now seemingly complete, the murderer unplugged the phone line, but then elected not to make good his escape. Instead for the next few hours, he chose to remain inside the house, carrying out a series of seemingly mundane tasks. Ignoring the bloodied and battered bodies of his four victims, he had located the family's first aid kit and then treated his injuries. But he made no effort to clean up the blood he had lost or to hide or conceal the dressings he had used. He simply left them lying on the floor in plain sight for the authorities to find.

Having cleaned and bandaged his minor cuts, the killer then moved into the family's kitchen, where he made himself a pot of barley tea. To go with his drink, he removed and ate some melon slices from the fridge, before going on to consume four ice creams from the freezer. After this, it seems the attacker went for a nap on one of the living room sofas for an hour or two. He then awoke and logged onto Mikoto's computer for a time, before using one of the toilets and making no effort to push away the waste he'd left behind and then finally exited the address in the early hours of New Year's Eve.

Discoveries of the Police

The police were quick to discover that the family's killer had left the broken murder weapon at the scene, which bore traces of both his blood and that of his victims. He had also inexplicably left a small bag lying on the floor, which contained highlighter pens and a small quantity of sand. All of these items were duly recovered and sent for forensic analysis in the hope of identifying the killer. And whilst, along with clothing fibers which were also discovered, they did provide vital clues as to the identity of the murderer, it quickly became clear that the hunt for him would not be an easy one.

The killer's DNA and fingerprints were both identified and analyzed, but did not match anything held within any of Japan's national databases. What could be ascertained from the analysis is that he was male and of mixed heritage, with one parent likely to have come from Southern Europe or the Mediterranean region. His blood was identified as type A and from the nature of the wounds he had caused to his victims, he was believed to be right-handed of a slim build and measuring roughly 170 centimeters tall.

Analysis of the force used to commit the murders produced an age range of between 15 and 35 years old, but beyond that, nothing more of a conclusive nature could be confirmed. Analysis of the fecal matter, which had so carelessly being left behind in the toilet at the crime scene indicated that at some point during the day, before he had committed the murders, the murderer had consumed a simple meal of string beans and sesame seeds. It would later be confirmed that both the kitchen knife used to commit the murders and the clothing that the killer had worn had been purchased somewhere in Japan's Kanagawa Prefecture, situated over an hour's drive away.

In time, the police were able to confirm the only 130 units of the sweater worn by the murderer had been made and sold, but frustratingly their inquiries would only lead them to 12 consumers who had purchased these garments. However, perhaps the most surprising and intriguing clue as to the attacker's identity would come from detailed analysis of the sand, which had been found inside the discarded bag. Scientists were able to narrow the source of this particular down to the Nevada desert in California, more specifically the area situated around the Edwards Airforce Base.

Hypotheses for the Senseless Killing of the Family

Since the time of the murders, there have been a number of different hypotheses put forward regarding who could be responsible for the senseless killing of this young and seemingly unassuming family. These vary somewhat in terms of their viability and credibility, and sadly, the nature of the evidence recovered by the police investigation appears so limited, that no single suggestion seems to be any more realistic than the rest.

Perhaps the most prevailing hypothesis suggests that the family fell victim to a stalker or sexual predator. The apparent discrepancy in the level of injury caused to the female members when compared to that of their male counterparts has led some psychologists to suggest that the killer likely possessed a pathological hatred of women.

Others have suggested that the extreme violence that was used against the family as a whole is more indicative of a crime of passion. Potentially, this was a man who was completely obsessed with Yasuko Miyazawa, or conceivably an associate of the family who believed they had been wronged or dishonored by them at some point in the past. But investigations into known sexual predators and crimes which have occurred since the slayings, as well as inquiries with friends and extended family of the victims, have not produced anything to escalate either of these theories beyond mere speculation. If the Miyazawa family were perhaps guilty of some past misdemeanor, then it has yet to be uncovered.

Looking outside of the family and its history, another popular theory is that the killer may have been a migrant or drifter. The location, like many of the houses in Japan was located a short walk from a transportation hub, causing some to believe that the killer was traveling around the country via its extensive rail network.

This chilling hypothesis is worryingly similar to that of the 'Man from the train' which we have previously covered. It is believed by some that a man named Paul Mueller was responsible for a series of killings in the Southwestern United States at the close of the eighteen hundreds, including the infamous Villisca Axe murders. He would allegedly travel by train through isolated rural areas in search of casual labor, before breaking into family homes and killing the occupants using their own tools.

Since the 1980s, Japan has seen an influx of immigration from neighboring Asian countries. In addition, the country has also developed an issue surrounding drifters. The 1990s were a time of serious financial instability in Japan, with many workers becoming unemployed or experiencing severe losses. Some of these people have never fully recovered from this and have elected never to re-engage with the society, that they feel so badly failed them.

Rather than someone associated with the Miyazawa family, is it possible that their targeting was instead completely random? That their house was picked because it was the first one that the killer had encountered as he had left the adjoining park, or that he had seen them out shopping and decided to follow them home on an impulse?

A similar theory involves the presence of the sand recovered from the bag left at the scene, which potentially links him to Edwards Air Force Base. This has led some commentators to assert that the murderer was one of the 50,000 US military personnel stationed in Japan at the time. Sadly, American servicemen and contractors have regularly been involved in high-profile crimes in the country, prompting national outrage, and a demand for their removal. With this to be the case, this theory would also comfortably explain the mixed DNA profile recovered from the killer.

But perhaps the most reaching theories about the murders pertain to the open space situated behind the family home. There have been suggestions that the Miyazawas had been offered up to a hundred million yen to move so that the authorities could demolish their house along with others in order to expand the park. There is also a rumor that in the weeks leading up to his death, Mikio had been involved in some form of altercation with the gang at the local skateboard park. Some believe that this may have led to either a biker or street gang murdering him and his family as a result of his disrespect.


At the time of writing, the Tokyo Metropolitan Police are still believed to have a task force of 35 officers assigned to solving the mystery of the Miyazawa family murders.

The investigation has secured over twelve and a half thousand different evidential exhibits, and there have been in excess of 15,000 tip-offs from members of the public to an information line set up by the police. After spending eight long years heading up the case, Takeshi Tsuchida was eventually forced to retire, but has continued to pursue the matter independently from the ongoing police investigation. And after 20 years of the police conducting an annual service of remembrance at the crime scene, it has recently been announced that the building will now be torn down due to the structural damage that has naturally occurred through neglect and lack of maintenance. Although the Miyazawa family home will soon be lost, sufficient detail and evidence from inside it has been suitably preserved, in the hope that the man responsible for the crimes which took place there will one day be identified and brought to justice. Our hearts go out to the relatives of the Miyazawa family. May their loved ones rest in peace!


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