Brazil blackouts result of cyber hacking: report

The CBS news program 60 Minutes said it had learned that the 2007 blackout in Espirito Santo State, which affected over three million people, and a smaller incident in Rio de Janeiro in 2005, were perpetrated by hackers.

The program, to be aired on Sunday, included the revelations as part of an investigation into the threat of cyber attacks on the United States.

Former Chief of US National Intelligence Mike McConnell told the 60 Minutes that he thought a similar attack is poised to take place on US soil.

If cyber hackers were able to infiltrate the US power grid, he said, "the United States is not prepared for such an attack."

Earlier this year the White House, State Department and Pentagon websites were among US government entities targeted in cyber attacks, amid suspicion that North Korea or its supporters are to blame.

In May South Korea and the United States agreed to cooperate in fighting cyber attacks against their defense networks.

Jim Lewis, director of the Center for Strategic and International Studies, emphasized to 60 Minutes that US cyber security has come under significant attack from foreign nations in the past few years, including a breach of the CENTCOM Network, the US command post heading the wars in Afghanistan and Iraq.

"We know it was a foreign country. We don't know which one -- this was a very sophisticated set of skills," Lewis told CBS.