This article is related to an article in The Register last week but provides a little more information concerning the types of attacks:
"Now new evidence has been discovered that indicates the same sort of political activism believed to have driven the 2007 Estonian Web site attacks not only exists but is becoming more popular.
"We spent some time after the Estonia attacks looking into this part of the world, and we've found evidence of other politically motivated botnet DOS attacks," said Jose Nazario, senior software engineer at Arbor. "It's hard to tell who is responsible for these campaigns, but they definitely appear to be tied to some recent Russian and Ukrainian elections."
Botnets: The new political activism