It was a DoS attack.

“The website of the newspaper Kommersant was subjected to a massive DoS attack, as a result of which the functioning of the Internet page of the publication was suspended. The attack on the Kommersant website began at around 3:00 pm Moscow time, and until now, specialists have failed to cope with the actions of the intruders. In a telephone conversation with the Lenta.Ru correspondent, Pavel Chernikov , the chief editor of the site, said that in this case, the possible methods of countering DoS attacks did not lead to positive results. According to Chernikov, today's attack may be a consequence of the morning publication of the transcript of the interrogation of Boris Berezovsky on the case of Alexander Litvinenko, however, the editor-in-chief of the Kommersant website stressed, there is no evidence of this version yet , ”Lenta.ru reports .

And Habr, by the way, was the first who informed about it ! Habrahabr !!!

PS By the way, yesterday the DoS-attack was also subjected to the site of the radio station Ekho Moskvy . So maybe these were pre-planned "teachings" of the special services, which simply coincided with the publication of the interrogation of Berezovsky.