Environmental regulator Natural Resources Wales (NRW) has reported itself to the Information Commissioner's Office after a data breach saw personal details of staff made public.
NRW said those affected had worked for it between April 2013 and March 2018.
A spreadsheet was inadvertently disclosed containing employee information that may have included diversity monitoring data, such as ethnicity, disability status, religion or belief, sexual orientation, Welsh language ability or caring responsibilities.
An NRW statement said: “As soon as we became aware of the issue, we took immediate steps to contain the incident and investigate the circumstances surrounding the disclosure.
“This included removing the information from the website where it had been published, obtaining confirmation that it had been permanently deleted, reviewing related published information to identify and address any similar risks, and reporting the matter to the Information Commissioner's Office (ICO) in line with our legal obligations.”
It said there was no evidence the information has been misused, but urged those affected to “remain vigilant for any unexpected communications and to report any concerns”.
