Under Polish law only a limited number of people, including historians and journalists, can access the files. However, the leak was sprung after Polish journalist Bronislaw Wildstein retrieved the names legally from the National Remembrance Institute (IPN) and distributed the information to colleagues. It is not known who went on to publish the list on the internet.
The IPN has said that people listed in the files are not automatically agents or collaborators and warned against using the names for political battles.
Politicians, preparing for parliamentary and presidential polls in the country, described Mr Wildstein's actions as 'irresponsible'.
More news from dotJournalism:
Polish national daily paper launched online
In from the cold
Old ghosts resurface to haunt UK government
More coverage:
Reuters
Free daily newsletter
If you like our news and feature articles, you can sign up to receive our free daily (Mon-Fri) email newsletter (mobile friendly).
Related articles
- Reuters launches AI-powered tool to speed up discovery of historic videos
- “Hey Google, tell me something good”
- Hazel Baker, head of UGC newsgathering at Reuters, on fighting covid-19 mis- and disinformation
- Reuters Connect partners with seven more national news agencies to localise its international coverage
- International news publishers frustrated with UK Brexit coverage as audiences demand better information