These may be repeat postings but here are links with some information I found to be of interest:
Twice a week, Miyazawa had traveled for two hours by train and bus from her home in Saitama Prefecture to take care of the children while her son and daughter-in-law worked.
When she exited the bus at a stop nearest to the house, the two children who were waiting outside would run toward her, saying, “Grandma.”
She let the children play in a park before she prepared dinner. They always ate all the food she cooked. The grandchildren baked cakes for her for Christmas and her birthday.
‘Why can’t it be solved?’ Still no suspect in 2000 killing of family | The Asahi Shimbun: Breaking News, Japan News and Analysis
The MPD suspects the motive was money and goods because bank cards and other items were found spread out in the home.
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The perpetrator is believed to be a male around 170 centimeters tall
Ex-detective in Setagaya family murders still supports mother | The Asahi Shimbun: Breaking News, Japan News and Analysis
around that same time, an eyewitnesses walking by the park that ran directly behind the Miyazawas’ house claimed to have heard the sounds of a family argument. The sounds, the eyewitness said, were coming from the Miyazawa house. Another eyewitness said that they saw some unidentified man run behind the Miyazawa house.[3]
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Police found that the killer’s clothes had been purchased in Kanagawa Prefecture but had been washed in a manner that was not common in Japan. This latter fact led many to believe that the killer was a foreign national.
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Prior to the murders, Mikio Miyazawa had engaged in several heated arguments with young skateboarders who frequented the skate park behind the family’s house. In particular, eyewitnesses said that Mikio often confronted the teenage skateboarders for making too much noise. One eyewitness also said that
that Mikio had done the same thing to members of a local motorcycle gang who were hanging out in the skate park.[7]
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Also, forensic testing of the clothes left behind by the killer at the crime scene indicated that they had been
washed with mineral-rich hard water, a type of cleaning water common in South Korea but uncommon in Japan.
10 Gruesome Facts Of The Setagaya Family Mystery - Listverse
On his clothes, there were traces of zelkova leaves and bird droppings. In his bum bag, there were sand grains from the Mojave desert, the other side of the planet.
The real life story behind Blue Light Yokohama: Part 2
the mother of Yasuko Miyazawa, who lived next door, repeatedly buzzed her daughter on the intercom.
New book claims to shed light on Setagaya family murders in 2000 - Japan Today
~The children waited on Grandma by themselves and played in the park by themselves twice a week presenting an opportunity for observation or contact.
~ Bank cards had been handled.
~ Is there something about the silhouette that isn’t right so no recognition? He looks tall and thin in the image, imo.
~ Argument heard in home: Perp comes to door is admitted some kind of argument takes place perp is ejected and runs behind the house to find access for revenge?
~Question: EAFB is on the western edge of the Mojave. Sand blows.
Could the sand have blown from EAFB into another area out of their bounds?
~ South Korean cleaning water?! Is it sold in Japan?
~This looks like Zelkova Trees in the picture of the skate park. Pictured next to 5
https://listverse.com/2018/08/04/10-gruesome-facts-of-the-setagaya-family-mystery/
Starling flocks, prolific poopers, roost in Zelkova. Evidence of perp spending time in the skate park?
~Ym’s Mother used intercom not phone to try to reach family
All imo