Investigators blame N. Korea for data leaks at S. Korean nuclear power plants

North Korea is believed to be the culprit behind recent data leaks from South Korea's nuclear power plants.
Last year, a group of hackers leaked documents about the facilities, including blueprints,... and last week, they released additional files and demanded money in return for not selling the information to other countries.
An interim probe found that the incidents were "aimed at inciting social unrest."
Investigators added that the leaked data was not critical information, and that it was obtained by hacking the email and online communities used by former officials of the Korea Hydro and Nuclear Power Company,... rather than directly from the operator's network.
The probe also found that malicious codes used in the cyber attacks were similar to those used by North Korea,... and the IP addresses used were based in the North.