Tokyo police have arrested a 31-year-old Chinese man accused of operating an SMS blaster from a car parked in Ginza, one of the city’s busiest shopping districts. Yu Hai was caught operating the device on the afternoon of 7 November and referred to prosecutors on 9 November for operating an unlicensed radio station and interfering with NTT Docomo’s network.
Police say the device disrupted mobile service within a radius of approximately 500 metres, causing phones to lose their normal network connections before connecting to the SMS blaster’s fake 2G network. Police estimate that the device disrupted service for more than 10,000 phones in less than two hours, including those belonging to officers investigating the case.
The SMS blaster sent Chinese-language smishing messages claiming that the recipient’s credit card had been suspended because of suspected overseas fraud. The messages contained links to a website designed to steal card details. Police have received complaints from 18 Chinese tourists and students since January 2025, involving losses of approximately JPY4mn (USD26,000). They are investigating whether Yu was responsible.
The car had previously been spotted behaving suspiciously in Ginza, Shinjuku and Shibuya, three areas popular with foreign visitors.
