Computer Networks in South Korea Are Paralyzed in Cyberattacks

Computer networks running three major South Korean banks and the country’s two largest broadcasters were paralyzed in attacks that some experts suspected originated in North Korea, which has consistently threatened to cripple its far richer neighbor.

The attacks, which left many South Koreans unable to withdraw money from A.T.M.’s and news broadcasting crews staring at blank computer screens, came as the North’s official Korean Central News Agency quoted the country’s leader, Kim Jong-un, as threatening to destroy government installations in the South, along with American bases in the Pacific. Though American officials dismissed those threats, they also noted that the broadcasters hit by the virus had been cited by the North before as potential targets. The Korea Communications Commission said that the disruption originated at an Internet provider address in China but that it was still not known who was responsible.