What is "cyberberkut"

CyberBerkut —is a modern organized group of pro-Russian hacktivists. The group became locally known for a series of publicity stunts and distributed denial-of-service (DDoS) attacks on Ukrainian government, and western or Ukrainian corporate websites. WHOIS query reveals that they have been using San Francisco based CloudFlare services via Whois Privacy Corp. registered in Nassau, Bahamas to hide their identity.