Tokyo police arrest two fiber-line sales agents over break-ins to rival's customer pages
In short
Tokyo Metropolitan Police arrested two employees of Ofisharu (オフィシャル), a fiber-line sales agency in Tokorozawa, Saitama, on suspicion of illegally accessing a rival's customer web pages and using the contract details to win customers over. Both admitted the allegations, police said. Police and the victim company put the scale at about 3,700 accesses since March 2023 and about 2,500 lost contracts, with losses of about 180 million yen a year.
Read the full story 2 min read
The Tokyo Metropolitan Police Department's cybercrime division has arrested two sales employees of Ofisharu (オフィシャル), a fiber-line sales agency in Tokorozawa, Saitama Prefecture, on suspicion of violating the Unauthorized Computer Access Act and the Unfair Competition Prevention Act. The suspects are Ai Kogo (向後愛), 38, and Mirai Oyama (大山未来), 40. Asahi Shimbun and Nikkei reported that police announced the arrests on October 8. Police said both admitted the allegations. [ 2 , 3 , 4 , 5 , 6 , 7 , 8 ]
According to the cybercrime division, as reported by Sankei Shimbun and ITmedia, the two obtained a customer list for internet provider hi-ho, based in Toshima Ward, Tokyo, from a list broker. They phoned hi-ho customers while posing as company staff to obtain personal details such as dates of birth. TBS NEWS DIG reported that they told customers that 'the company at the time no longer exists and there is no contact desk' and that 'a name and date of birth are needed to tell you your current plan'. Jiji Press reported that they abused a feature that lets customers who forget their ID log in with a postal code or date of birth. Nippon TV said they obtained login details from customers such as restaurants. [ 1 , 2 , 5 , 6 , 7 , 8 ]
Once logged in, they checked contract plans, options and monthly fees and urged customers to switch, saying that changing provider would be cheaper. Sankei and ITmedia reported the pitch as '1,100 yen cheaper'. The arrest charges cover accesses on October 3, 2025 and February 13, 2026. [ 1 , 2 , 5 , 6 , 7 , 8 ]
The victim company told police that about 3,700 'My Page' accounts had been accessed since March 2023 and that about 2,500 customers had switched, causing losses of about 180 million yen a year, Asahi reported. TBS NEWS DIG reported that police believe the damage reaches that annual amount. Jiji said police are investigating whether the 3,700 accesses led to the 2,500 switches. Asahi said the case came to light after the victim saw a large number of contracts move to a competitor. [ 2 , 3 , 6 , 7 ]
Asahi described Ofisharu as a sales agency for a telecom operator that provides fiber-line services to businesses and competes with the victim. Jiji described Ofisharu itself as a fiber-line operator. TBS NEWS DIG reported that Oyama told investigators he had carried out improper sales activity 'several times before'. [ 2 , 3 , 6 , 7 ]
Why it matters
The case shows how a password-recovery feature that lets customers log in with a postal code or date of birth was used to read a competitor's contract data, according to Jiji Press. Police brought charges under both the Unauthorized Computer Access Act and the Unfair Competition Prevention Act, treating the customer data as trade secrets.
Key facts
- The Tokyo Metropolitan Police Department's cybercrime division arrested Ai Kogo (向後愛), 38, and Mirai Oyama (大山未来), 40, both of Tokorozawa, Saitama Prefecture. [ 2 , 3 , 4 , 5 , 6 , 7 , 8 ]
- The two worked for Ofisharu (オフィシャル), a fiber-line sales agency based in Tokorozawa. [ 2 , 3 , 5 , 6 , 7 , 8 ]
- They are suspected of violating the Unauthorized Computer Access Act and the Unfair Competition Prevention Act. [ 2 , 3 , 4 , 5 , 6 , 7 , 8 ]
- Posing as the rival's staff, they phoned customers to obtain details such as dates of birth, then logged into the customers' 'My Page' accounts to see plans and monthly fees. [ 2 , 5 , 6 , 7 , 8 ]
- The arrest charges cover accesses on October 3, 2025 and February 13, 2026. [ 5 , 8 ]
- About 3,700 accesses since March 2023 are believed to have led to about 2,500 contract cancellations. [ 2 , 3 , 6 , 7 ]
- Losses are put at about 180 million yen a year. [ 3 , 6 , 7 ]
- Both suspects admitted the allegations, police said. [ 1 , 2 , 3 , 5 , 6 , 7 , 8 ]
Confirmed by several sources
- Two Ofisharu employees, aged 38 and 40, were arrested by the Tokyo Metropolitan Police Department. [ 2 , 3 , 4 , 5 , 6 , 7 , 8 ]
- The charges are under the Unauthorized Computer Access Act and the Unfair Competition Prevention Act. [ 2 , 3 , 4 , 5 , 6 , 7 , 8 ]
- Both suspects admitted the allegations. [ 1 , 2 , 3 , 5 , 6 , 7 , 8 ]
- The victim company is internet provider hi-ho. [ 5 , 8 ]
- About 3,700 accesses since March 2023 and about 2,500 lost contracts are under investigation. [ 2 , 3 , 6 , 7 ]
- Losses are estimated at about 180 million yen a year. [ 3 , 6 , 7 ]
Still unclear
- Whether all of the roughly 2,500 contract cancellations resulted from the suspects' actions. Jiji and Sankei say police are still investigating the link; Asahi attributes the figures to the victim company.
- Ofisharu's exact role. Asahi and others call it a sales agency for another operator; Jiji calls it a fiber-line operator.
- How the customer list was obtained. Only Sankei and ITmedia, which carry the same text, report that it came from a list broker.
What local media are saying
Timeline, local time
- Nippon TV reports the arrest of two sales agency employees over unauthorized logins. [ 1 ]
- Jiji Press reports the charges and the scale of about 3,700 accesses. [ 2 ]
- Asahi Shimbun reports police announced the arrests and cites losses of about 180 million yen a year. [ 3 ]
- Sankei Shimbun names hi-ho as the victim company. [ 5 ]