Japanese criminals have been recruiting accomplices on social media for years, but their work just got a little tougher thanks to a new police tactic: using AI to find them before a crime is committed.
Officers with Tokyo’s Metropolitan Police Department (MPD) have been deploying AI to automatically detect criminal recruiting posts on X.
The force introduced AI tactics in July. The system studies slang terms and stock phrases in such ads including “legitimate opportunities” and “same-day payment in cash”.
It classifies suspicious posts on X by risk level, which is followed by a review by officers. Even with that step, the system is a lot more efficient than manual searches.
The force was able to increase its average number of warnings sent daily over posts from about 25 to 150. In the four months from August to November, officers sent out warnings to X users regarding some 18,500 posts, more than double the approximately 9,000 sent in all of last year, according to the MPD.
Posts are often deleted after warnings are issued. The force plans to expand its use of AI to other social media platforms including Meta’s Threads.
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As ranks of old-school yakuza organised crime syndicates have dwindled, police are fighting a new class of offenders called tokuryu, a term meaning “anonymous and fluid criminal groups”.
Tokuryu recruit accomplices on an ad hoc basis. They have drawn attention for online offers of part-time, seemingly innocuous jobs promising easy money, known as yami baito, or “dark gigs”.
Once an applicant provides their personal information, the recruiter can threaten their family or friends if they don’t do the work, which turns out to be criminal in nature.
On Friday, police announced the arrest of four men suspected of masterminding a series of robberies in the Tokyo metropolitan area, including one assault that left a 51-year-old woman in Chiba Prefecture seriously injured.
The four, Hiroto Fukuchi, 26, Takuya Saito, 26, Karura Murakami, 27, and Shota Watanabe, 26, allegedly recruited accomplices on X and issued instructions through the encrypted Signal app. They purchased X accounts multiple times to recruit perpetrators, according to investigators.
The gang allegedly committed 18 robberies in Tokyo and the neighbouring Chiba, Saitama and Kanagawa prefectures between August and November last year, which led to the arrests of dozens of other suspects.
AloJapan.com