Transcript for Who Was Behind Sony Hack?
Thank you. Move on to the latest on the Sony hacking scandal. The government expected to blame North Korea for the destructive attack today as we learn more about the evidence building up to make the case. Pierre Thomas is tracking the investigation. Good morning. Reporter: Good morning, George. There was an attempt by the hackers to cover their trail. But today sources tell us the U.S. Has evidence pointing to North Korea. ABC news learned that investigators found two critical pieces of evidence linking north Korea to the attack. They discovered the assault had specific signatures of a north korean-style hack. And they found the hack was identical to a series of attacks targeting south Korean banks and other institutions last year. The U.S. Government is certain that those attacks were carried on on behalf of North Korea. Intelligence officials believe the assault was unprecedented. An extraordinary act of aggression. It's being used as a weapon. Reporter: Sources familiar with the investigation tell ugh the electronic assault from North Korea was routed through a number of infected computers overseas. Singapore, tailand, tlaet, Bolivia, Poland and cypress. The president considers it to be a serious national security matter. It's being treated as such. Reporter: To cloud the trail, they had a group outside the country to launch the attack. Likely part of the elite north Korean spy unit bureau 121, tasked with an army of cyber wear years. Recruited as children and trained at this military school. It included this threat to American movie Goers. Remember the 11th of September 2001. All apparently because the north Koreans are angry about a movie depicting the assassination of their leader. So the big question, what's the U.S. Government going to do about it? There is a precedent here. When those Chinese hackers were active earlier this year, the U.S. Government moved to indict them. Yes, they charged Chinese leaders for hacking American companies they're considering the same thing in this case, but not there yet.
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