“Of course, at the moment, I cannot state for certain that the cyber attacks were managed by the Kremlin, or other Russian government agencies,” said Estonia’s Defense Minister, Jaak Aaviksoo, on the Estonian Kanal 2 TV channel.

Here is the story is reported from two angles: Police conclude probe into alleged riot ringleaders (Baltic Times)
and
Estonia towns down claims (Moscow news)

Connected story: NATO Examines (Russian) Cyber Attacks on Estonia

…and I cannot state for certain Martians are green but we all know they are don’t we?