Crime, Betrayal, and Hidden Informants: Inside the Natural Gang

A shock ran through the Tokyo Metropolitan Police Department

Daisuke Jinbo (43), a police inspector in the Anti-Organized Crime Division, was arrested on November 12 on suspicion of violating the Local Public Service Act for leaking investigative information to Natural, the largest and most notorious illegal scouting group in Japan. At the time, police were conducting nationwide crackdowns on Natural, considered an anonymous and fluid-type criminal organization, and it emerged that a key investigator had instead been compromised by the group.

According to Metropolitan Police sources, the charges allege that Jinbo sent images from surveillance cameras he had installed to monitor Natural members to the group. It is also suspected that he leaked other investigative information in exchange for compensation.

Natural reportedly has nearly 2,000 members nationwide, mainly young people in their 20s. The group recruits women to work in adult entertainment establishments and receives illegal referral fees, called scoutbacks,” from the establishments, generating annual revenue estimated at around 5 billion yen.

The organization exerts strict internal control through violence. FRIDAY has previously reported on its operations twice. Rumors of an insider had been circulating for nearly a year. In late January, a task force led by the Anti-Organized Crime Division attempted a coordinated arrest of Natural executives, but when they raided an apartment where members were believed to be hiding, the targets had already fled. Investigators recalled:

“We had thoroughly monitored the targets, including top executives, and even conducted behavior checks at upscale restaurants in Tokyo’s entertainment districts. But at the moment of execution, all targets were suddenly unaccounted for. It could only mean our information had been completely leaked.”

Jinbo had been a central member of this investigation team. Sources describe him as always being very fond of women. He was divorced, had a young child with his new spouse, and was rumored to be involved with another woman. He had recently purchased a luxury car, raising suspicions about his finances.

How does Natural manage to recruit police insiders? The most common method is through organized crime intermediaries.

“Jinbo had long been responsible for organized crime investigations, working as a so-called Maru-Bou officer, whose job included obtaining information from within criminal groups. It is said that through an introduction from a gang member he was friendly with, he came into contact with executives of Natural,” a source familiar with organized crime said.

Some adult entertainment establishments where Natural sends women maintain friendly relations with police, which can also serve as an introduction. A current member, speaking on condition of anonymity, explained:

“Professional countermeasures are handled by specialized police units with abundant resources. Insiders are bribed with large sums of money. Once a person’s sense of money is warped, they cannot operate without our cash—similar to women falling into the adult entertainment industry. Investigation information is shared only with executives, and only necessary information is passed on to members.”

We even have high‑ranking police officials as informants

When the Metropolitan Police searched Jimbo’s home, they found ¥9 million in cash in a drawer. It is believed that money was regularly handed over in exchange for investigative information, and an active member bragged, “I’ve heard the amount sometimes reached several million yen a month.”

On Jimbo’s smartphone was a special app used exclusively by members of Natural. It is said to be extremely secure and to have been independently developed at a cost of tens of millions of yen, modeled on overseas apps.

“It has all the basic functions—chat, file sharing, and calls—and insiders conduct all communications through this app. To obtain it, someone from headquarters has to be present and download it using a special method. Basically, outsiders can’t use it. In emergencies, the app can even be remotely deleted from the phone so that no evidence is left behind,” the same source said.

Jimbo was removed from the Natural investigation this spring, and from summer onward he was questioned voluntarily, effectively placed in a de facto suspension. However, within Natural, investigative information was reportedly still being shared afterward. Another active member said:

“In September, there was talk that it looks like the collaborator inside the Metropolitan Police might get exposed. Even so, investigative information is still being leaked as usual. I can’t go into details, but in a certain prefecture in the Kanto region, there’s a high‑ranking police official we’ve had a long relationship with, and in major cities nationwide there are multiple routes. There are still plenty of informants.”

As he said this, he showed an app screen containing quite detailed information about police raids and searches.

There are still many others who have been compromised. Police authorities are aware of the critical situation, and internal investigations are reportedly under way, including in regional forces. The Metropolitan Police are working to identify the Natural executives who were exchanging information with Jimbo and are searching for their whereabouts.

One senior police official stated emphatically:

“At this point, we have no choice but to go all the way, even if it means shedding blood. Dismantling Natural—one of the largest and most malicious among the tokuryu (anonymous, fluid criminal) groups—is our top priority.”

The spread of “Natural contamination” within the police. The depth of that darkness remains impossible to measure.
(Honorifics omitted in part.)

From the December 12, 2025 issue of “FRIDAY”