<figure id="attachment_463816" class="wp-caption alignnone" style="width: 813px;" aria-describedby="caption-attachment-463816"><a href="#" data-ident_hash="8d27b961"><img src="https://res.cloudinary.com/fridaydigital/image/private/t_article_image/wpmedia/2026/04/4fe6b56c131d6f4aba0dd8833f3a764c.jpg" alt=""></a><figcaption id="caption-attachment-463816" class="wp-caption-text">The man arrested on suspicion of attempted extortion, Masanori Kurihara</figcaption></figure>
<h2>Extortion attempt with a survival knife</h2>
<p data-start="301" data-end="500">With silver-streaked romance gray hair slicked back from the top to the back of his head and a beard, the man walked straight ahead as he was guided by police officers, holding his posture upright.</p>
<p data-start="502" data-end="783">At first glance, he even looked like a company president due to his imposing presence. This man is Masanori Kurihara, who was arrested on April 2 by Totsuka Police Station of the Metropolitan Police Department on suspicion of attempted extortion and sent to prosecutors on April 3.</p>
<p data-start="785" data-end="1561"><strong>“According to the Metropolitan Police Department, Kurihara is a member of an organization affiliated with the designated crime syndicate Sumiyoshi-kai, specifically the Kohei-ikka faction. Kurihara and another member are suspected of threatening a man in his 50s on a street in Shinjuku Ward while showing what appeared to be a survival knife and demanding money. They allegedly told the victim things such as, ‘What happened to the 3 million yen you gave earlier?’ and ‘Kidnap him. Stab him,’ while demanding money. The victim fled to a nearby convenience store, asked a clerk for help, and called 110. Kurihara and the other suspect left the scene but were later found in Tokyo and arrested on the 1st,”</strong> said a reporter from a national newspaper’s social affairs department.</p>
<p data-start="1563" data-end="2184">In fact, just three days earlier, on March 31, the Metropolitan Police Department had announced the arrest of five members, including a leader of a group under the same Kohei-ikka faction, on suspicion of confinement and robbery causing injury. The suspects allegedly confined a former member of the same organization in a room in a building in Toshima Ward, Tokyo, from the night of February 22 to the morning of the 23rd, assaulted him, and stole necklaces and other items worth about 900,000 yen, causing serious injuries that required one month to heal. The victim reportedly left the organization after the incident.</p>
<p data-start="2186" data-end="2588">The Metropolitan Police Department established a special task force in January this year, stating that Kohei-ikka was involved with so-called “Tokuryu” (anonymous and mobile criminal groups) engaged in special fraud and so-called dark part-time job robberies, and other crimes. On April 1, command authority was upgraded from the Criminal Affairs Bureau director to the Deputy Superintendent General.</p>
<p data-start="2590" data-end="2786">Within the span of three days before and after this, two separate arrests of members connected to Kohei-ikka occurred. A journalist specializing in the underworld, Yukio Ishihara, was interviewed.</p>
<div data-friday-nextpage-lead="The &quot;Kouhei Family&quot; by name."></div>
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<h2>An organization skilled in Tokuryu crime</h2>
<p data-start="44" data-end="340"><strong>“Until now, incidents that normally wouldn’t make the news are being properly disclosed by the Metropolitan Police Department. Rather than broadly labeling them as ‘Sumiyoshi-kai,’ the police specifically named ‘Kohei-ikka.’ You really get the sense of a strong determination to go all the way.</strong></p>
<p data-start="342" data-end="695"><strong>In January 2023, there was a robbery-murder case in Komae, Tokyo involving Tokuryu groups, which has since become a major social issue. One of the known hubs of Tokuryu activity is Kabukicho in Shinjuku, Tokyo, and in the same year the Commissioner of the National Police Agency even conducted patrols there, making it a priority area for investigation.</strong></p>
<p data-start="697" data-end="904"><strong>Kabukicho is also one of Kohei-ikka’s territories, and it is known to have strong ties with networks related to the former Kanto Rengo. In other words, it is an organization highly skilled in Tokuryu crimes.</strong></p>
<p data-start="906" data-end="1235"><strong>Their major sources of income include acting as masterminds behind special fraud schemes and human trafficking carried out through Kabukicho scouting operations. The decision to specifically name Kohei-ikka and investigate and arrest related individuals in order to strike at those core revenue streams is extremely significant.”</strong></p>
<p data-start="1237" data-end="1507">In the past, there have been cases where an organization leader is arrested under employer liability and a search warrant is executed, but investigations rarely reached the true top-level orchestrators behind Tokuryu networks. However, this case is said to be different.</p>
<p data-start="1509" data-end="1893"><strong>“In the past, in similar cases, rival groups would sometimes leak information to the police to have their enemies taken down. But this time is completely different. The police are publicly signaling we are going after Kohei-ikka nationwide and steadily executing it. This is not something other groups can ignore anymore. There is no doubt they are now thinking, ‘Maybe we’re next.’</strong></p>
<p data-start="1895" data-end="2063"><strong>The police likely also feel a sense of responsibility for having long tolerated dark part-time job crimes, so it seems they are finally getting serious,”</strong> said Ishihara.</p>
<p data-start="2065" data-end="2240" data-is-last-node="" data-is-only-node="">Whether the Metropolitan Police can truly dismantle Tokuryu networks remains to be seen. Kurihara and the other suspect deny the allegations, and the investigation is ongoing.</p>
<div data-friday-nextpage-lead="Members of the Kouhei Family to be sent to prosecution."></div>
<figure id="attachment_463818" class="wp-caption alignnone" style="width: 983px;" aria-describedby="caption-attachment-463818"><a href="#" data-ident_hash="619aed68"><img src="https://res.cloudinary.com/fridaydigital/image/private/t_article_image/wpmedia/2026/04/b2507913a9437fa0e37933fd81f2b9c2.jpg" alt=""></a><figcaption id="caption-attachment-463818" class="wp-caption-text">On April 3, the suspect Masanori Kurihara came out of the Totsuka Police Station of the Metropolitan Police Department to be sent for inspection.</figcaption></figure>
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<figure id="attachment_463820" class="wp-caption alignnone" style="width: 1048px;" aria-describedby="caption-attachment-463820"><a href="#" data-ident_hash="68541eb1"><img src="https://res.cloudinary.com/fridaydigital/image/private/t_article_image/wpmedia/2026/04/f0128cca79c91e296a277685222ee770.jpg" alt=""></a><figcaption id="caption-attachment-463820" class="wp-caption-text">He was stoutly built and walked with dignity.</figcaption></figure>
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<figure id="attachment_463821" class="wp-caption alignnone" style="width: 899px;" aria-describedby="caption-attachment-463821"><a href="#" data-ident_hash="4467f553"><img src="https://res.cloudinary.com/fridaydigital/image/private/t_article_image/wpmedia/2026/04/d904adbd303c4f0deefc019ff8b76676.jpg" alt=""></a><figcaption id="caption-attachment-463821" class="wp-caption-text">Masanori Kurihara denies the charges.</figcaption></figure>


 Shinji Hasuo

 The Metropolitan Police Department set up a "special task force" naming the Kouhei Family, the central organization of the Sumiyoshikai. A member of its umbrella organization was arrested on suspicion of attempted extortion by threatening him with a survival knife. Three days earlier, a group leader and others affiliated with the same organization had also been arrested.

Tokyo Police Launch Special Task Force After Key Arrests—Crackdown Intensifies Against Tokuryū Criminal Network

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