A nuclear plant operator in South Korea is initiating precautionary drills to fend off cyberattacks following a breach that led to extortion threats, according to a report on the BBC site.

The mitigation efforts are a reaction to the posting online last week – from the "president of the anti-nuclear reactor group" – of the plant's designs and machine manuals. The threat to Korea Hydro and Nuclear Power Co. (KHNP) warned that unless the reactors were shut down people should "stay away" from them, the BBC report said.

While KHNP said the purloined data did not compromise the plant's safety, it will conduct extensive drills at four of its complexes next week.

The ease of access to infrastructure assets, subsequent to materials being connected to the internet, has been a risk that many security experts have been warning about for years.