The blogger, who told the newspaper that his first name is Georgy and that he is a 34-year-old economics lecturer, said that the hackers sent hundreds of thousands of e-mail messages, falsely saying they came from him and asking recipients to visit his pages on Twitter, LiveJournal and Facebook.

On Friday, a spokeswoman for Facebook told IDG News Service that Thursday's attack "appears to be directed at an individual who has a presence on a number of sites, rather than the sites themselves."

"Specifically, the person is an activist blogger and a botnet was directed to request his pages at such a rate that it impacted service for other users. We’ve isolated the issue and almost all of our users are able to enjoy the normal Facebook experience," she said via e-mail.

A source close to Facebook further told IDG News Service on Friday that the attack was aimed at a specific user based in Georgia.