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Bill Radke: A fresh wave of cyber attacks that slowed U.S. and South Korean Web sites this week hit more targets this morning. A Web security firm says access from South Korea to the U.S. State and Defense Departments appeared to be disabled. Marketplace's Dan Grech reports these attacks have hit both government and business Web sites. The U.S. and South Korea are looking for their source.
Dan Grech: Earlier attacks hit 14 sites in the U.S., including the White House, the New York Stock Exchange, and online retailer Amazon.com.
Tens of thousands of computers were infected by a virus spread by e-mail. The virus caused the computers to flood the targeted Web sites with traffic in an attempt to shut them down.
Officials say the cyber attacks were relatively rudimentary, and no sensitive information was lost. But the attacks were massive in scale. There's speculation North Korea may be behind them. The communist nation is reportedly running a cyber warfare unit to gather military intelligence from the U.S. and South Korea.
Experts say it can be difficult to source a cyber offensive, because attackers can mask their location and identity.
I'm Dan Grech for Marketplace.