The figure jumped more than tenfold from the 669 cases reported in a shorter period between April and December in 2017, when it became mandatory for cryptocurrency exchange operators to report transactions suspected to be linked to the movement of illegally obtained cash.
Cryptocurrency can be transferred quickly and largely anonymously, with police saying that in some cases virtual currency was used to pay for illegal drugs or child pornography.
Among the 7,096 suspicious transactions, some users with different names and birth dates shared the same ID photo, while others appeared to log into their accounts from overseas even though their listed addresses were in Japan.
Including all financial transactions, 417,465 cases of suspected money laundering or other abuse were reported to the police in 2018, up 17,422 from a year earlier. Most of them involved banks and other financial institutions, which made 346,014 reports in total, followed by credit card companies, with 15,114 cases reported.
After analyzing the reports, the NPA provided information on 8,259 cases to investigating authorities, up 1,096 from a year earlier. As a result, police handled 1,124 cases, mainly involving fraud.