A global cyber war could cause destruction on the scale of an atomic war and lead to the death of millions, an online expert says.
US cyber security expert Scott Borg has told a conference cyber attackers could completely destroy power generators using malicious software code.
While a loss of electric power for a few days may cause limited damage, a widespread shutdown beyond eight to ten days could effectively halt a nation's economy for months.
"If you shut down the economy to that degree, we're not talking about people being inconvenienced," Mr Borg told the Australian Defence Magazine Cyber Security summit in Canberra.
"In America, it's hundreds of thousands — maybe millions — die.
"For any other part of the world it's similar destruction."
Food and medicine distribution would be affected, along with transport and access to other so-called necessities of life such as heating.
Similar attacks could be mounted against other critical infrastructure such as oil pipelines or refineries, railways and the financial sector.
"We are talking about nuclear exchange level destruction by pure cyber attack," Mr Borg added.
"You can do just awesome damage to a country with pure cyber attacks."
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