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April 27, 1999
Web posted at: 11:53 a.m. EDT (1553 GMT)

(CNN) -- The CIH computer virus, also called the Chernobyl virus, is believed to have paralyzed hundreds of thousands of personal computers in Asia when it activated on Monday.

In South Korea, government officials say up to 240,000 computers were affected.

"Two to three percent of eight million PCs in use domestically are estimated to have been infected (with the virus)," the Information and Communication Ministry said in a statement Tuesday.

But media reports said officials at local anti-virus program development companies estimated the virus may have hit as many as 600,000 PCs.

The ministry said anti-virus program developers received reports of infection from about 1,000 private companies, 200 government and public organizations and 300 universities.

In China, state-run media said more than 100,000 computers have been affected, with more than 5 percent of them badly damaged.

An official at China's largest maker of anti-virus software reportedly said his company has been inundated by calls from computer users from all over China.

"All of our telephones have been busy since yesterday," Liu Xu, a general manager at Ruixin Co., was quoted as saying.

Xinhua said three strands of the virus have been reported in China: one designed to strike Monday, one on June 26 and one on the 26th of every month.

The virus, believed to have originated in Taiwan last summer, attempts to erase a computer's hard drive and damage the computer's system settings. The most common strands are programmed to activate on computers using Windows 95 and Windows 98.

Unlike the recent "Melissa" virus, which spread itself via e-mail but did no direct damage, the Chernobyl virus didn't propagate as quickly because it required a person to open an infected file to contaminate a computer.

The April version of the virus is particularly damaging because it can also keep a computer from starting up by infecting the software on which all the PCs programs depend, the basic input/output system, or BIOS.

The virus is called the Chernobyl virus because it is timed to go off on the anniversary of the 1986 Russian nuclear accident, one of technology's worst disasters.

The Associated Press and Reuters contributed to this report.