“I Had to Make Him Pay”—Inside the Suspect’s Deadly Rage in the Ōmori Apartment Case

The body of the man was found stabbed multiple times

The man, sitting in the center of the back seat of the transport vehicle, had his hair parted and wore glasses, different from when he had been transferred to the Tokyo Metropolitan Police Headquarters the previous night. He had kept his head down the whole time, but for a brief moment he lifted his face and looked at us. His eyes were sharp, glaring at the camera.

The person sent to prosecutors on the morning of January 10 was Masahiro Yamanaka (45), the sales manager of an audio equipment company. He had been arrested on the 9th on suspicion of murdering the company president, Akihiro Kawashima, in a condominium in Ota Ward, Tokyo. The incident came to light around 11:30 a.m. on the 8th.

“A friend who visited the condominium because Kawashima had not shown up at the scheduled time reported it to the police. Officers found Kawashima inside, lying in a pool of blood. He had been stabbed several times, including in the neck and abdomen, and there were also injuries on both hands, likely from resisting,” said a reporter from a national newspaper’s social affairs desk.

Bloodstains and bloody footprints were confirmed in the hallway and entrance, and since the weapon was not found inside, the Metropolitan Police Department’s First Investigative Division determined it was a murder case and established a special investigation unit at the Omori Police Station.

Immediately after the incident on the 8th, Yamanaka was questioned and denied involvement. However, due to inconsistencies in his statements, the investigation headquarters kept him under surveillance. The following day, January 9, at 6 a.m., he left his home and went to Tokyo Station to try to buy a Shinkansen ticket, prompting police to request voluntary accompaniment.

“Security camera footage also confirmed Yamanaka entering and leaving the condominium. Later, he hinted at the killing, saying things like, ‘I was dissatisfied with Kawashima’s usual attitude, so I visited his home to speak my mind. We struggled, and I stabbed him with a fruit knife I brought from home,’ and, ‘I sprayed insecticide in the entrance, and when he flinched, I stabbed him in the neck. I chased him as he tried to escape and attacked him from behind.’ He was arrested based on these statements. He also partially denied the charges, saying, ‘I did stab him, but I didn’t intend to kill him,’” the same source added.

A 30-Year Friendship

Kawashima and suspect Yamanaka had a boss-subordinate relationship at work, but they had been high school classmates and friends for 30 years.

“They called each other ‘Aki-chan’ and ‘Ma-’ and often went on drinking trips and vacations together. About eight years ago, Kawashima even attended Yamanaka’s wedding. Yamanaka had been moving between jobs in advertising and apparel, but around four years ago, Kawashima asked him to join his current company, saying, ‘I want to improve the company. I want you to act as a bridge with the employees.’ The treatment there was reportedly better than his previous jobs,” said a crime reporter.

However, after working together as boss and subordinate, tensions gradually arose between the two.

“They hardly went to the places they used to drink together anymore. Yamanaka’s mother told reporters, ‘He seemed dissatisfied with his work,’ and Yamanaka himself stated that he was unhappy with Kawashima’s lack of gratitude toward employees and poor language. Since his complaints didn’t get through, he said, ‘If words don’t work, I thought it was necessary to make him reconsider even if it meant making him feel pain.’

He also stated, ‘My bonus, which had been one and a half months, was reduced to one month, and I wasn’t given a reason,’” the same source added.

On the night of the 7th, Yamanaka reportedly waited for Kawashima to return home within the condominium grounds, then visited his apartment and attacked him. When entering the building, he had changed clothes from what he wore when leaving home, and after the crime, he appears to have changed back inside the apartment. He then went to a restaurant and drank with friends until the early hours. The weapon and the clothes he wore during the attack were later found in the trash area of another condominium.

When did the gap appear?

Why did suspect Yamanaka commit such a violent act against a friend he had once been close to? Crime journalist Taihei Ogawa offers the following analysis:

“For a salaried worker, no matter how good the workplace, there will always be some dissatisfaction with one’s boss. Still, because there is a hierarchical relationship between boss and subordinate, most people tolerate it.

But in this case, they were friends who had known each other for a long time. A friendship is stronger than a boss-subordinate relationship, so you can say what you want. That can be a good thing, but there is no hierarchy established there. What would normally be ‘He’s the boss, so it can’t be helped’ turns into ‘Who does he think he is?’

Conversely, because the boss was a classmate, he may have felt he could say anything, even scold him harshly in front of other employees. As the president, he might have thought he could do this because he trusted Yamanaka, but in reality, it didn’t work that way. Those emotional gaps had likely grown large.

However, breaking into someone’s home with a weapon is abnormal. Moreover, the fact that he prepared a change of clothes anticipating blood stains, disposed of the weapon, and discarded it at the trash area of another condominium shows premeditation as well.”

Was the emotional gap caused by moving from a friendship to a boss-subordinate relationship really that significant? Investigators are expected to reveal more as the case develops.