More than 90,0000 passwords of private email accounts in Sweden, including those of politicians, celebrities and editors, have been leaked by an anonymous hacker, The Guardian reports.

In addition, 57 other websites had been hacked, jeopardizing up to 180,000 Swedish accounts, The Local reports.

The hacker, known under the alias “sc3a5j,” told the Expressen newspaper in an email that he leaked the private accounts “ to let people know that they handle their information wrongly.” The leak is considered to be Sweden’s worst data leak in history.

Account information of Swedish political journalists were also leaked through the Twitter account of William Petzäll, a Swedish politician. Petzäll denies being involved with the leak.

"It's a story about the possible naivety of Swedish internet users who log into their bank account and the New York Times web pages using the same password," Expressen journalist Micke Ölander told The Guardian.

Computer security experts are urging users of Bloggtoppen.se and the other sites to change passwords to their accounts on those sites and others.