SEOUL (BNO NEWS) — Ten of thousands of virus-contaminated personal computers in South Korea are programmed to “self-destruct” on Friday, government officials warn.

The warning comes after a third consecutive day of cyber attacks against South Korean government websites, taking many of them offline for hours. U.S. government websites, including websites of the White House, the U.S. State Department and the New York Stock Exchange, have experienced similar attacks over the past week. None of them were affected.

Both South Korea and the United States have said they suspect the North Korean government to be behind the cyber attacks.

But the cyber attacks are now said to enter a new phase, the Yonhap news wire reported on early Friday. “The Korea Communications Commission (KCC) said it has been notified by computer vaccine company Ahn Lab that the so-called “distributed denial-of-service” (DDoS) virus, which is responsible for initiating the ongoing cyberspace war in South Korea, was set to destroy at least 20,000 contaminated PCs across the nation,” a report from the news agency said.

The report said the virus has been programmed to automatically destroy the computer’s stored data starting Friday. It did not say if any foreign computers had been infected by the virus.