The Singapore Land Authority has disclosed a data security incident involving unauthorized access to IBM-managed cloud development and testing environment, exposing personal data, according to a ministry release on Sunday.

The data breach resulted in the exposure of names, NRICS numbers and property addresses of around 70,000 individuals in a dataset that should have contained only anonymized mock data, the release said.

The dataset was created in 1998 and was updated periodically for vendor development and testing of SLA's automated registration and eLodgment systems, according to the release.

IBM has also revoked access to the compromised environment.