Overwatch has faced issues of Aimbot and hacking in the last several weeks. It has caused several problems to the players who have not been able to experience a fair gameplay. Despite Korea having a strict legislation against cheating and using illegal methods in gameplay; the legislation has not yet become active.
In a bold move, Blizzard has decided to ban almost 10000 players who have been guilty of using the cheats.
Nuking, in particular, is already illegal in Korea (when classified as a DDOS) according to Article 48 of the Promotion of Information and Communication Network Utilization and Information Protection Act. Fines for doing so can run up to 50 million won, or about $43,000 USD.
Source : Korea BattleNet