Computer networks of several major South Korea broadcasters and banks have been paralyzed. Police and government agencies are investigating what appears to be a cyberattack.
The shutdowns in Seoul on Wednesday come days after North Korea blamed South Korea and the United States for cyberattacks that temporarily shut down websites in Pyongyang. Tensions between the countries are high over the North's nuclear ambitions.
Officials at the two public broadcasters KBS and MBC said that all computers at their companies shut down at 2pm. (6pm NZT).
The officials declined to give their names, saying they were not authorized to speak media.
YTN cable news channel reported the company's internal computer network was completely paralyzed.