Arcadia Inc. reports possible leak of up to 3.1 million municipal client records

Arcadia Inc., which helps municipalities send disaster alerts and other emergency information, announced that unauthorized access to its computer system may have resulted in the exposure of up to 3.1 million records containing email addresses and telephone numbers. The company suspended certain services after detecting the suspicious access on Sunday and is working to assess the full scope of the breach. This leak occurs amid a series of recent data security incidents in Japan, such as Central Japan Railway Co.'s disclosure that personal information of roughly 15,000 e-commerce users may have been accessed, though credit-card data remained safe.

The affected data were stored by IDC Frontier Inc., a subsidiary of SoftBank Corp., which recently suffered a ransomware attack that disrupted cloud services for 495 companies and municipalities. Authorities and the firms involved are investigating the cause and potential impact on residents and local authorities.