A hacker stole the entire data of the residents of the country of Austria.
The 25-year old Dutchman who was arrested in Amsterdam had presented the 9 million data sets that included full names, genders, addresses and date of births.
Authorities believe the information has mostly likely fallen into the hands of shady entities. The revelations come 3 months after the arrest in a bid to control fears that it might evoke.
The same hacker had also stolen and tried to sell data for Italy, the Netherlands and Colombia.
He presented them for sale in May 2020.
Fortunately, the information posted online did not include financial information.
"Since this data was freely available on the Internet, it must absolutely be assumed that these registration data are, in full or in part, irrevocably in the hands of criminals," the police said, adding that unknown people were believed to have paid for the data.
The hacker was already known to the international police (Interpol).
Austria has a population of 9 million.
The police did not elaborate on the consequences for Austrians' data security.