For the second time in recent history Russia has flexed both its military and cyber muscles. The latest incident is playing out in The Autonomous Republic of Crimea (Ukraine) The previous incident occurred in South Ossetia (Georgia) in 2008. Russia has also flexed its cyber power in the former Soviet states of Estonia (2007) and Kyrgyzstan. The Russian military has the capability to employ sophisticated electronic warfare techniques (e.g., jamming), which would disrupt cellular communications within Ukraine.”]
Source: https://www.darkreading.com/attacks-breaches/a-cyber-history-of-the-ukraine-conflict