Tokyo Metropolitan Bureau of Waterworks Reports Four Missing Hard Drives and Contractor Loss of Customer Documents

According to Security NEXT, the Tokyo Metropolitan Bureau of Waterworks discovered on October 2, 2026, that only empty storage boxes remained inside a locked cabinet while four hard drives were missing ^[1]. The hard drives stored land management and utilization data containing the names of 1,932 corporate, government, and resident individuals, with some records also including addresses or phone numbers ^[1]. In a separate incident on October 20, an outsourced contractor employee left a bag on a train, losing documents containing names, addresses, phone numbers, and interaction logs for 84 customer households ^[1].

Industries mainly affected: Government

In a separate incident on October 20, an outsourced contractor employee left a bag on a train, losing documents containing names, addresses, phone numbers, and interaction logs for 84 customer households ^[1].