Kofu Incident: A Creepy Alien Got off a UFO to a Vineyard and Tapped a Japanese Boy on the Shoulder in 1975 [Part 1]

Sponsored Links

This is the true story of Japanese boys who encountered a creepy alien who got off a UFO to a vineyard in 1975.

In the history of UFO incidents in Japan, the Kofu Incident is called one of the two major UFO incidents in Japan, along with the Kera Incident which I introduced in the article below.

The Kofu Incident is an incident in which two eight-year-old Japanese boys allegedly had direct contact with a UFO and aliens in Kofu City, Yamanashi Prefecture, Japan in 1975.

The Kofu Incident is considered to be the most credible case of contact with aliens in Japan, as there are several pieces of physical evidence that a UFO landed there, and it is also supported by the eyewitness accounts of several other adults. For this reason, many UFO researchers and UFO enthusiasts in Japan still visit and investigate the vineyard near Hinode Danchi (Hinode Complex), the site of the Kofu Incident, almost 50 years after it occurred.

Thus, the Kofu Incident is one of the most famous and important UFO incidents in the history of Japanese UFO incidents, along with the Kera Incident in 1972. Nevertheless, outside of Japan, although the outline of the Kofu Incident is known, the details of the incident are not so well known.

So in this article, I would like to present the whole story of the Kofu Incident as accurately and in detail as possible, based on various reliable primary sources (that is, reports obtained through direct interviews with the boys and their families who were involved in the incident at the time).

Strangely enough, even though all of those reports were obtained by directly interviewing the boys who witnessed the incident, the content of their accounts differs slightly from interviewer to interviewer. Therefore, in this article, I have tried to organize those reports consistently, but if there were multiple conflicting accounts, I have tried to include them as Notes.

In addition, to ensure the accuracy of this article, I have included a list of references (all written in Japanese) at the end of this article. If you are interested in the details of the Kofu Incident, please make use of this list.

I hope this article will be helpful to those who are interested in UFO cases in Japan.

On August 15, 2021


Kofu Incident: Amazing Experiences of Japanese Boys Who Directly Encountered Aliens Who Got off a UFO

The Location Where the Kofu Incident Took Place

On February 23, 1975, the Kofu Incident took place in Kami-Cho, Kofu City, Yamanashi Prefecture, Japan.

Yamanashi Prefecture is the western neighbor of Tokyo.

Kofu City is the capital of Yamanashi Prefecture and is located roughly in the center of Yamanashi Prefecture.

Kofu City is a long north-south region, stretching 41.6 km from north to south, and 23.1 km from east to west, and is a longitudinal basin sandwiched between mountains on the north and south sides.

The eastern part of Kofu City is famous for its vineyards and grapes.

And Kamicho, where the Kofu Incident took place, is also located in the eastern part of Kofu City.

Below is an aerial view of Kamicho, Kofu City, where the Kofu Incident took place.

In 1975, when the Kofu Incident occurred, Kofu City already had a population of about 194,000.

In terms of population size, Kofu City is equivalent to Rochester, New York, USA.

Members of the Kono and Yamahata Families Involved in the Kofu Incident

The Kono Family

Masato Kono (A eight-year-old boy who encountered aliens)

Masako Kono (Masato’s mother)

Toshihiro Kono (Masato’s father)

*** Kono (Masato’s younger brother)

The Yamahata Family

Katsuhiro Yamahata (A eight-year-old boy who also encountered aliens, and a classmate of Masato’s.)

Hanae Yamahata (Katsuhiro’s mother)

Minoru Yamahata (Katsuhiro’s father)

Michihiro Yamahata (Katsuhiro’s older brother)

*** Yamahata (Katsuhiro’s four-year-old sister)

Flight Routes of Two UFOs That Allegedly Flew over Kofu City on February 23, 1975

Below is a map showing the UFO sighting and landing sites in the Kofu Incident, created based on aerial photographs taken by the Geospatial Information Authority of Japan’s Ministry of Land, Infrastructure, Transport, and Tourism on November 30, 1975, the same year the Kofu Incident occurred.

The following map was created from a 1975 aerial photograph of Kofu City by the Geospatial Information Authority of Japan, using Kubota’s information as a reference. 
Source: Geospatial Information Authority of Japan

As shown in this map, two orange UFOs, one large (UFO-1) and one small (UFO-2), approached the employment promotion housing (Kamicho housing complex) from the southeast and hovered over the housing for a while.

The larger UFO then flew directly north toward Mt. Atago, while the smaller UFO flew northeast to a vineyard and landed there.

Japanese Boys Witnessed Two Orange UFOs in Kofu City on February 23, 1975

At around 6:30 p.m. on February 23, 1975, two eight-year-old Japanese boys, Masato Kono and Katsuhiro Yamahata, living in Kofu City, Yamanashi Prefecture, Japan, were playing on roller skates in a vacant lot near Employment Promotion Housing (currently Kofu Municipal Kamicho housing complex. Hereafter referred to as Kamicho housing complex) in Kamicho, Kofu-City.

Katsuhiro Yamahata (left) and Masato Kono (right)

Masato and Katsuhiro*1 were classmates in the second grade of Yamashiro Elementary School in Kofu City, and also because it was Sunday, they were playing until later than usual.

Masato’s father, Toshihiro Kono, and Katsuhiro’s father, Minoru Yamahata, were brothers-in-law, so Masato and Katsuhiro were cousins.

Kamicho Housing of the Employment Promotion Agency (currently Kofu Municipal Kamicho housing complex) in 1975.
The site southeast of the Kami-Cho Housing where Masato and Katsuhiro played with roller skates at the time.

When Masato and Katsuhiro looked up at the darkening sky, they noticed two shining orange objects*2, one large and one small, floating in the sky above Mt. Tatsuzawa in the east.

The above image is for illustrative purposes only.

According to Hiroshi Minamiyama, a Japanese writer and researcher of strange phenomena, two blue-white lights flew soundlessly toward the two boys from the eastern sky.  One of them immediately flew away toward Mt. Atago in the north, but the other one came closer and closer to the boys, shaped like a “saucer,” and emitted an orange light above their heads.
On the other hand, according to an interview with Shinichiro Namiki and Kazuo Hayashi of the Japan Space Phenomena Society (JSPS), Katsuhiro was the first to discover the UFO.

The UFO flew from the east-southeast of Kofu City, that is, from the direction of the snow-covered Tanzawa Mountain in the center of the photo below.

At first, the two objects looked like mere lights, but as the boys watched, the orange objects came closer and closer to where they were.

Eventually, the two objects reached the sky above the Kamicho housing complex, made a big turn, and then hovered over the heads of the boys who were watching them in amazement.

Sketch of the UFO in flight by Masato and Katsuhiro.  The Japanese words “Sora wo Tondeiru Enban” on the far left mean “Saucer flying in the sky.”

According to Masato and Katsuhiro, the object was circular in shape when viewed from below, and had three spinning devices at the bottom.

Sketch of the bottom of the UFO seen by Masato and Katsuhiro, showing the three circular landing gears.
Masato (left) and Katsuhiro (right) draw a sketch of the UFO for the explanation.

At that moment, the two boys immediately realized that they were saucer-shaped UFOs. Then, from the bottom center of the hovering UFO, they saw a black tubular object stretching toward the ground.

According to the boys, the black object stretched out while making clattering noises twice. Shortly after, they heard what sounded like a camera shutter clicking.

The above image is for illustrative purposes only.

When Masato and Katsuhiro saw the black tubular object emitting sounds, they first thought they were being targeted with a weapon like a gun. The boys were so terrified that they took off their roller skates and fled to the nearby graveyard of Daiyuzan Fukuo Temple.

Masato and Katsuhiro recreate the scene of their hiding place in the graveyard of Fukuo Temple. The boys held out their palms to show the size of the UFO they could see from them.

Masato and Katsuhiro hid behind tombstones in the darkened cemetery, holding their breath and staring in horror at the hovering UFOs. The UFOs stayed there and hovered for a while.

As Masato and Katsuhiro watched the UFOs, the larger one soon flew northeast toward Mt. Atago, but the smaller one flew away in the direction of a vineyard. Relieved that the UFOs had left, the boys left the cemetery and headed to Masato’s house*3.

Masato’s house was located in the Hinode Complex.

The Boys’ Route after the UFO Sighting

The route Masato and Katsuhiro took from the site of the first sighting of the two UFOs to the vineyard where one of the UFOs landed.  The following map was created from a 1975 aerial photograph of Kofu City by the Geospatial Information Authority of Japan, using Minamiyama’s information as a reference.
Source: Geospatial Information Authority of Japan

Masato and Katsuhiro Observed the UFO up close during the Landing

As Masato and Katsuhiro came to the road on the west side of the Hinode Complex, they saw a bright red flame in the darkness ahead*4.

The above image is for illustrative purposes only.

According to an interview with Namiki and Hayashi of the JSPS, Katsuhiro was the first to discover the red flame.


As soon as they thought that, the boys forgot about the earlier UFO encounter and started running toward the red flame.

The road led to a dirt road, and beyond that were vineyards. The vineyards, however, were fallow because it was winter, and there were no vines, only concrete poles standing wildly in the open.

Today, the vineyard where the Kofu incident took place is no longer there, and a building of Mokko Land Co., Ltd. has been built on the land. However, there is still a vineyard in the vicinity, and you can still see the vestiges of the vineyard from that time.

According to Masato and Katsuhiro, they could see the red light flickering in the vineyard.

But the moment the boys approached a few dozen meters (a few dozen yards) in front of it, the red light somehow quickly slid sideways to the center of the vineyard and rapidly turned into a pale light*5.

The above image is for illustrative purposes only.

According to Kubota, as Masato and Katsuhiro passed by a vineyard, they saw an orange light again in the middle of the vineyard 60-70 meters (about 66-77 yards) away.  It was the same light that the UFO had been emitting earlier.  The orange light blinked repeatedly, but eventually, it faded.
On the other hand, according to Namiki and Hayashi, the object took off, flew up to a considerable height, and then descended again, passing through a gap in the concrete supports of the vineyard and landing near the center of the vineyard.
As these reports show, there are minor discrepancies in the accounts of the boys given by different interviewers, including Kubota, Minamiyama, Namiki, and Yaoi.

After the light faded, what the boys saw was a silver UFO that landed in the vineyard!

Katsuhiro (left) and Masato (right) explain how the UFO landed in the vineyard.

Although they had been terrified just a moment ago, the boys couldn’t resist their curiosity and approached the UFO.

According to Masato and Katsuhiro, the UFO was shaped like a round dome on top of a flat plate lying upside down, with several shining blue square windows surrounding the dome.

Sketch of the UFO during landing by Masato and Katsuhiro.  The Japanese words “Chakuriku Siteiru Enban” on the far left mean “Saucer during landing.”

When the boys stood in front of the UFO, only the upper dome part was rotating, but it eventually stopped. The windows around the dome were translucent, with black frames separating the windows. The surface of the UFO’s body was silver, like stainless steel, and seemed to glow dimly.

The size of the UFO was about the size of an ordinary passenger car, with the main body of the UFO about 2.5 meters (about 8 feet) in diameter and 1.5 meters (about 5 feet) in height, according to visual measurements.

Masato and Katsuhiro raise their right hands upward to indicate the height of the UFO.

According to Masato and Katsuhiro, there was no sound of the UFO moving and the area was quiet, but sand flew up while they were looking at the UFO.

The boys were so curious that they observed each part of the UFO in detail for about five minutes. At that time, Masato, who was observing the UFO from about one meter (about three feet) away from the east side, noticed strange characters written on the surface of the UFO’s body.

Characters written on the UFO’s body

According to Masato, they were black characters that appeared to be slightly raised, as if stickers had been put on the body. They looked like a kind of hieroglyphics. Masato said that at first, he interpreted these five characters, which the boys called “space characters,” to mean “(flying) saucer.”

Those characters were also on the opposite side of the UFO. According to Katsuhiro, he went around the UFO and noticed similar characters written on the other side, that is, the west side.

But unfortunately, the exact shape of the characters on the other side is unknown because Katsuhiro, who was looking at the UFO from the other side, was not sure of his memory. Later, Katsuhiro tried to recreate the characters on the other side of the UFO based on his vague memory of the time, but he could not remember the shape of half of them and could not recreate them properly.

First there’s the letter A, then there’s the letter B to connect to it, then the letter C …

And I don’t know the rest …

According to Katsuhiro, those characters were like capital letters of the alphabet connected, as shown in the sketch below.

Characters written on the other side of the UFO’s body.

Masato crouched down to observe the bottom of the UFO and found three semicircular spherical landing gears at its bottom. According to Masato, those gears were about 25 centimeters (about 10 inches) high and were in full contact with the ground. He then stood up again and was looking with interest at the strange characters on the body of the UFO.

Suddenly, the door next to the characters slammed open from above towards the front, and a staircase appeared in front of him! According to Masato, when the door slammed down, the inside of the door was a staircase. He also said that when the door opened, there was a clattering sound, like a lock being opened.

Sketch of the UFO during landing by Masato and Katsuhiro. The meanings of the Japanese words in the sketch are as follows. (A) Masato Kono, (B) window, (C) 7 steps, (D) characters, (E) Yamahata (F) window, (G) characters.

The moment the door opened, Masato saw the dimly lit interior of the UFO. According to Masato, the interior of the UFO was filled with machinery and instruments, with red, blue, and green lights flashing.

The above image is for illustrative purposes only.

Masato and Katsuhiro Encountered a Creepy Alien Who Got off the UFO

Masato was startled and looked through the door to the inside of the UFO, where he saw a small alien with a creepy face standing there!

According to Masato, the alien was about 130 to 135 centimeters (about 4.3 to 4.4 feet) tall. The alien’s head and shoulders were unusually large compared to the rest of its body, and its head was brown and bald with nothing that looked like hair on its head. The alien’s face was brown, but it had no eyes or nose as if it was wearing a mask.

Sketch of the alien seen from the front

The alien had a strange, undulating face with several deep black horizontal wrinkles about the thickness of a pinky finger. According to Masato and Katsuhiro, the alien looked like it was wearing a mask. In addition, the alien had no mouth-like features, but on the part of its face where a mouth should be, three silver fang-like teeth were growing downward about 5 centimeters (about 2 inches) long.

Furthermore, it had four-fingered hands, wore shoes with two divided toes, and its ears were long and large like a rabbit’s, but with a hole in the middle. The alien’s hands were brown and had deep wavy wrinkles on their surface, similar to those on its face, making them look like gloves.

The alien was dressed in a silver suit that connected its entire body into one piece, with a gray belt around its waist and what looked like a gun with an open-end like a trumpet slung over its left shoulder.

Sketch of the alien and the gun-like object that the alien had hanging from its left shoulder
Sketch of the alien by Masato and Katsuhiro. The meanings of the Japanese words in the sketch are as follows. (A) Masato Kono, (B) brown, (C) brown, (D) yellow, (E) silver (F) Yamahata, (G) ray gun.

According to Masato and Katsuhiro, the alien’s silver suit was connected to the mask on its face, and they could see what appeared to be a zipper on its backside.

Sketch of the alien seen from the back

Then the alien came down the stairs with slightly bow legs. However, according to Masato, somehow he did not hear the sound of the alien walking. The alien landed on the ground from the stairs and stood facing almost directly in front of Masato.

The alien might kill me!

Masato was struck with a sense of dread.

Katsuhiro Was Tapped on the Shoulder by the Alien

Katsuhiro, on the other hand, was observing the UFO from the other side at this time.

Sketch showing the position of Masato (in the front) and Katsuhiro (on the back) who were observing the UFO.

Suddenly, there was a clattering sound on Masato’s side, so Katsuhiro went around the UFO in the direction of the sound. At that moment, someone tapped Katsuhiro on the shoulder twice from behind.

Thinking it was Masato, Katsuhiro turned around and saw the ugly face of the alien, which was the same as the one Masato had seen!

The above image is for illustrative purposes only.

According to Katsuhiro, the alien held what looked like a gun in its right hand and tapped him twice on the left shoulder with its left hand.

Masato (left) and Katsuhiro (right) demonstrating what it is like to be tapped on the shoulder by an alien.

Also, based on the feeling of the alien touching his shoulder, the number of fingers on the alien was four. The alien cried out in a strange, squeaking voice. According to Katsuhiro, the voice sounded like a cassette tape recorder playing back at high speed.

In a later interview, Masato answered no to Kubota’s question about whether the alien spoke Japanese. The two boys said that the alien spoke to them then, but they did not understand what it meant. Nevertheless, they thought that the alien might have said hello to them.

Masato and Katsuhiro Witnessed Another Alien Operating the Controls inside the UFO

Katsuhiro was so startled and terrified that he collapsed to the ground. Then, realizing the danger he would be in if he continued to face the alien, he pretended to be dead. However, while pretending to be dead, he opened his eyes slightly and observed the alien. According to Katsuhiro, the alien was walking around at a fast pace and seemed to be observing various things around the UFO.

Then Masato came rushing from the other side. While the alien was looking elsewhere, Masato ran to Katsuhiro and helped him to sit up, and shouted at him.

Katsuhiro! Run away!

But Katsuhiro, frozen in fear, could not get up.

No, I can’t!!

Then Masato said to Katsuhiro,

Get on my back!

So Katsuhiro put himself on Masato’s back. Then Masato ran away from the vineyard with Katsuhiro on his back.

When they reached one end of the vineyard, Masato let Katsuhiro off his back and turned around. Then, through the open door of the UFO, they could see the inside.

The above image is for illustrative purposes only.

According to Masato and Katsuhiro, inside the UFO, another alien was sitting in a chair, holding a control stick and operating some kind of machine while watching a TV-like monitor in front of it.

Sketch of the inside of the UFO as seen from outside the door by Masato and Katsuhiro

The appearance of the alien inside the UFO was the same as that of the alien outside, but it was slightly shorter in height and had unusually long arms. Also, the wall behind the alien was filled with many complex instruments such as meters and gauges. According to Masato and Katsuhiro, they could not see the inside of the UFO through the windows.

The boys stared at the inside of the UFO for perhaps three minutes while suppressing the urge to run away immediately. However, perhaps sensing the boy’s presence, the alien in the chair suddenly turned and looked at them! So they panicked and rushed off again.

After that, Masato and Katsuhiro ran away without looking back and rushed into Masato’s house, gasping for breath.

Did the Boys Really Encounter Aliens?

In this article, I have described some of the Japanese boys’ amazing UFO sightings and alien encounters.

Unfortunately, in the Kofu Incident, there are no photographs of the UFOs or aliens that the boys witnessed. Therefore, some people may consider the accounts of the two boys fake.

However, the characters that were said to have been drawn on the body of the UFO and the descriptions of UFOs and aliens that the two boys said they observed were very detailed and consistent and seem to be too well done for the fantasies of eight-year-old boys.

According to Kubota, who interviewed the two boys, there was something consistent about their stories, and they always answered his questions crisply.

The boys’ sketches of UFOs resembled Adamski-type UFOs, so Kubota, who was a devotee of Adamski at the time, once showed the boys a picture of an Adamski-type UFO.

The above image is for illustrative purposes only.

However, Masato pointed to the sphere atop the dome of the Adamski UFO in the photo and said,

There is nothing like this (in the UFOs I saw).
The windows of the UFO were not round, but square.
The center of the bottom was not this big. But there were three landing gears just like this one.

Thus, when Kubota misinterpreted the shape and other aspects of the UFO that the boys witnessed, the boys even tried to correct his mistakes.

Also, on the night of the incident, the boys’ mothers and many other adults witnessed the mysterious light-emitting object.

Did the boys really encounter aliens?

In the next article, I would like to introduce the sighting of the mysterious light-emitting object by the mothers of the boys and how the Kofu incident became known throughout Japan.

Published on August 15, 2021
Updated on May 31, 2023
Written by OTAKUPAPA


  1. Hachiro Kubota (June 1975). UFO to Uchu (UFOs & Space) June 1975 NO.12, 8-17, Universe Publishing Co.
  2. Shinichiro Namiki (May 1975). Mikakunin Hikou Buttai – Jouhou to Sono Kenkyu – Gougai (Unidentified Flying Objects – Information and Research – Special Issue) No.2, Japan Space Phenomena Society (JSPS).
  3. Junichi Yaoi (July 1978). Zenkoku UFO Mokugeki Tahatsu Chitai (UFO Sighting Zones in Japan), 194-197, Futami Shobo
  4. Hiroshi Minamiyama, (May 1982). Uchu kara no Shinnyusha (Intruder from Space), 187-204, Futami Shobo
  5. Tomomi Saionji, (August 1989). Sekai UFO Daihyakka (World UFO Encyclopedia), 108-111, Gakken
  6. Monogusa Taro, (Mar 2004). Ummo Seijin GOGO!! (Ummo Alien GOGO!!) (Broken Link) Archived September 26, 2008, at the Wayback Machine
  7. Shinichiro Namiki (Feburary 2010). Mikakunin Hikou Buttai UFO Taizen (The Complete Guide to Unidentified Flying Objects UFOs), 238-244, Gakken Plus.
  8. Miyabi, (November 8, 2015), Kofu Incident, UFO Jikenbo (UFO Case Files),
  9. MYSTERY PHOTONICLE (May 2016), 42-43, Digital Ultra Project
  10. Tatsuya Honjo, ASIOS (August 2017). UFO Jiken Chronicle (Chronicle of UFO Incidents), 153-163, Saizusha.
Let's share this post !

Author of this article

A dad blogger who loves manga, anime, games. In this blog, I will introduce amazing Japanese spirituality and philosophy.


To comment


This site uses Akismet to reduce spam. Learn how your comment data is processed.