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Medium reported severity Criminal Charges

Japan: police say two teenagers used generative AI to build a fake payment-service site that took women's details, later used to pay for a hotel and consoles

Shiga prefectural police sent two teenagers' cases to prosecutors on 27 October 2026 on suspicion of violating Japan's unauthorised computer access law. According to the police announcement as reported by the Yomiuri Shimbun and Asahi Broadcasting (ABC), on 13 September 2026 the two, in Tokyo, sent two women the URL of a site made to look like a real payment service, told them they could receive money, and had them enter details such as email addresses and phone numbers. Police say the two used generative AI to make the phishing site, and the Yomiuri reports that one of them, who is believed to have used generative AI to make the fake site, said he did not have the skill to build a site without AI. The same day, police say, they logged into a travel-booking site with one woman's details and paid a Tokyo hotel bill of 182,830 yen; they were later re-arrested over three portable game consoles bought with another woman's account. Police believe they took about 50 people's information, including from other payment services, and charged about 5 million yen. Both admitted the allegations, according to the police. They are not named here.

AI system
Unidentified website-generation tool
Occurred
13 Sept 2026
Reported
27 October 2026
Event location
Japan
What the AI did
Communicated with the person
Reported harm
Other Material Harm
Whose AI use
Someone else’s AI use
Setting
Finance · Privacy · Everyday life
Evidence
AI involvement reported · Causal attribution alleged · 2 sources, 1 underlying account
5 claims: 5 reported. 4 open questions
People reported harmed
At least 2 people

AI system as recorded: Generative AI that, according to Shiga prefectural police, the suspects used to make a phishing site imitating a real payment service; the tool is not named

What Happened

What the police allege. Shiga prefectural police's cybercrime division announced on 27 October 2026 that it had sent the cases of two teenagers to the district prosecutors on suspicion of violating the unauthorised computer access law. According to the announcement as reported by the Yomiuri Shimbun, on 13 September 2026 the two, in Tokyo, sent two women the URL of a site made to resemble a real payment service, told them they could receive cash, and had them enter details such as their email addresses and phone numbers. ABC reports police saying the site was set up so that entered personal details reached the two at once.

How AI was involved. ABC reports that, according to the police, the two used generative AI to create the phishing site. The Yomiuri reports that one of the two is believed to have used generative AI to make the fake site and other things, and that he said he had no skill to build a site without AI. The police announcement does not name the AI tool or say what it produced beyond the site, and its basis for the attribution is not stated beyond the suspect's statement.

What followed. The same day, police say, the two logged into a travel-booking site with one woman's details and paid a Tokyo hotel bill of 182,830 yen; they were arrested on 17 September on suspicion of computer fraud. On 7 October they were re-arrested on suspicion of theft for buying three portable game consoles (95,940 yen in total) with another woman's account on a shopping site. Police believe the two took about 50 people's information, including account details for other payment services, and made about 5 million yen in payments, which they used for goods to resell and hotel bills. Both admitted the allegations, according to the police.

What is not known. The sources do not say whether the women or the payment services bore the charges, whether any money was recovered, which AI tool was used or whether all of the roughly 50 people were reached through the AI-built site.

Reported harm

According to the police, women who entered their details on a fake payment-service site made with generative AI had those details taken and their accounts used to pay a 182,830-yen hotel bill and buy game consoles; police believe about 50 people's information was taken and about 5 million yen charged.

How Harm Occurred

According to the police, a phishing site that the suspects made with generative AI imitated a real payment service; women who received its URL entered their personal details, which reached the suspects and were used to log into the women's accounts and pay for a hotel stay and goods.

Outcome

Pending

The two were arrested on 17 September 2026 on suspicion of computer fraud over the hotel payment and re-arrested on 7 October on suspicion of theft over the game consoles, according to the Yomiuri. On 27 October 2026 Shiga prefectural police's cybercrime division sent their cases to the district prosecutors on suspicion of violating the unauthorised computer access law. No indictment or juvenile-court outcome is reported as of 28 October 2026.

What remains unknown

  • Which generative AI tool was used and which parts of the site it produced.
  • Whether the women or the payment and booking services bore the charges, and whether any money was recovered.
  • How many of the roughly 50 people reached the AI-built site, as opposed to other routes.
  • Whether prosecutors indict the two or refer them to family court.

What the evidence supports

AI involvement: reported. Shiga prefectural police, the party that investigated the case, say the two suspects used generative AI to create the phishing site (ABC), and the Yomiuri reports that one suspect, believed to have used generative AI to make the fake site, said he could not build a site without AI. That site presented itself to the women as a real payment service, and they entered their details on it; police say the details reached the suspects and were used to pay for a hotel stay and buy game consoles. The AI-built site is the content the women relied on (communicated_with). The AI tool is not named, the police's technical basis is not stated beyond the suspect's statement, and the sources do not say which parts of the site the AI produced.

5 claims: 5 reported. What the statuses mean

Reported According to Shiga prefectural police, on 13 September 2026 the two suspects, in Tokyo, sent women the URL of a site made to resemble a real payment service, told them they could receive money, and had them enter details such as email addresses and phone numbers; the site passed entered details to the suspects at once.

Causal attribution. The police allegations as relayed by two outlets from one announcement; not tested in court.

  • yomiuri.co.jp(opens in new tab) supports · Japanese
    '男２人は９月１３日、東京都内で実在の決済サービスに似せたサイトのＵＲＬを女性２人に送信し、現金を受け取れる旨を伝えた上で、メールアドレスや電話番号などを入力させて取得した疑い。'
  • asahi.co.jp(opens in new tab) supports · Japanese
    'サイトに個人情報が入力されると即座に２人に情報が流れる仕組みにしていたということです。'
Reported Police say the two used generative AI to create the phishing site; one of them, who police believe used generative AI to make the fake site, said he had no skill to build a site without AI.

Causal attribution. Police attribution relayed by two outlets from one announcement, with a suspect statement relayed by one; the AI tool is not named.

  • asahi.co.jp(opens in new tab) supports · Japanese
    '２人は生成ＡＩを使ってフィッシングサイトを作成し'
  • yomiuri.co.jp(opens in new tab) supports · Japanese
    '男２人のうち１人が、偽サイトの作成などに生成ＡＩを使用したとみられ、「ＡＩを使わずにサイトを作る技術はない」と話しているという。'
Reported Police say the two used one woman's details to log into a travel-booking site and pay a Tokyo hotel bill of 182,830 yen, and another woman's account to buy three portable game consoles; they were arrested on 17 September and re-arrested on 7 October 2026.

Causal attribution. Police allegations relayed by two outlets; the figures come from the Yomiuri only.

  • yomiuri.co.jp(opens in new tab) supports · Japanese
    '旅行予約サイトに不正取得した女性の情報でログインし、都内のホテルの宿泊代金１８万２８３０円を決済したとして同１７日に電子計算機使用詐欺の疑いで逮捕。' 'もう１人の女性のアカウント情報を用い、オンラインショッピングサイトで携帯用ゲーム機３台（計９万５９４０円）を購入して盗んだとして窃盗の容疑で再逮捕されていた。'
  • asahi.co.jp(opens in new tab) supports · Japanese
    'ゲーム機３点を購入したなどの疑いで、先月以降２度逮捕されています。'
Reported Police believe the two obtained about 50 people's information, including account information for other payment services, and made about 5 million yen in payments.

Causal attribution. Police estimate relayed by one outlet; approximate.

  • yomiuri.co.jp(opens in new tab) supports · Japanese
    '２人は他の決済サービスのアカウント情報を含めて約５０人の情報を取得し、約５００万円を決済。'
Reported On 27 October 2026 Shiga prefectural police sent the two teenagers' cases to prosecutors on suspicion of violating the unauthorised computer access law; both admitted the allegations, according to the police.

Causal attribution. Police announcement relayed by two outlets.

  • yomiuri.co.jp(opens in new tab) supports · Japanese
    '滋賀県警サイバー犯罪対策課は２７日、'; '１０代の男２人を不正アクセス禁止法違反の容疑で地検に書類送検した。' '男２人は「間違いありません」と容疑を認めている。'
  • asahi.co.jp(opens in new tab) supports · Japanese
    '２人は、警察の調べに対し「間違いありません」と容疑を認めています。'

Sources

2 sources inspected, from 1 underlying account. Sources that repeat one account do not corroborate each other.

How the sources were read, and where the events happened

Read in Japanese by the research agent (an AI) on 2026-10-28 and translated by the research agent (an AI) into English; no human translator or reviewer was involved. The Yomiuri reports the Shiga prefectural police announcement. Applies to s1.

Read in Japanese by the research agent (an AI) on 2026-10-28 and translated by the research agent (an AI) into English; no human translator or reviewer was involved. ABC reports the same police announcement. Applies to s2.

Event countries: Japan. Affected-person countries: Unknown. Court countries: Unknown.

The Yomiuri reports police saying the two sent the URL while in Tokyo and paid for a Tokyo hotel with a woman's details; Shiga prefectural police investigated, so the event country is Japan. The sources do not say where the women or the other people whose information was taken live, so affected-person countries are left empty.

Reviewed for publication 2026-10-28: Published as a core case (communicated_with): Shiga prefectural police say two teenagers used generative AI to make a phishing site imitating a real payment service; women who were sent its URL entered their details, which police say were used to pay for a hotel stay and game consoles. One suspect is reported to have said he could not build a site without AI. The claims are the police's allegations as reported; no person is named.

People described

Women who were sent the fake site's URL and entered their details, two of whom are described in the police allegations; police say about 50 people's information was taken in total. No victim is named.

People reported harmed in this case

At least 2 people

0 AI participants · 2 other people harmed

Additional affected people are described without a reliable count.

The police allegations describe two women who were sent the URL and entered their details on 13 September 2026. Police also believe about 50 people's information was taken, including for other payment services; that figure is approximate and is not linked person by person to the AI-built site, so two people are counted and the rest are an unquantified remainder.

Counted once within this case. The same person may appear in other cases. This count does not establish AI causation.

Tags

#generative-ai#phishing-site#payment-service-impersonation#account-takeover#police-referral#japan

Cite this case

Compiled per our published methodology: verification statuses, sourcing standards, and corrections process.

APA

NOPE. (2026). Japan: police say two teenagers used generative AI to build a fake payment-service site that took women's details, later used to pay for a hotel and consoles. AI incidents. https://nope.net/incidents/2026-japan-shiga-police-say-two-teens-used-generative-ai-to-build-fake-payment-site-that-took-womens-details-used-for-purchases

BibTeX

@misc{2026_japan_shiga_police_say_two_teens_used_generative_ai_to_build_fake_payment_site_that_took_womens_details_used_for_purchases,
  title = {Japan: police say two teenagers used generative AI to build a fake payment-service site that took women's details, later used to pay for a hotel and consoles},
  author = {NOPE},
  year = {2026},
  howpublished = {AI incidents},
  url = {https://nope.net/incidents/2026-japan-shiga-police-say-two-teens-used-generative-ai-to-build-fake-payment-site-that-took-womens-details-used-for-purchases}
}

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