Recently Demonoid, Wikileaks & KrebsOnSecurity websites were hit by DDoS attacks. Demonoid never got back & was permanently shut down by authorities. While Wikileaks & KrebsOnSecurity came back online after the DDoS attack was over. This increase in DDoS attacks could be just an increasing random trend or specifically targeted act done by a group of individuals. No one has taken any responsibilities for these DDoS attacks. Distributed denial of service (DDoS) attack is an attack on a web server in which a large number of junk requests from many computers are sent simultaneously to the server thus making it unavailable for real users.

Are these attacks done by Authorities? This will be a question unanswered.
The only people who will gain anything from these attacks are Officials.

Source:Demonoid, Wikileaks, KrebsOnSecurity hit by DDoS