tokyo. it sounds like a bad movie but it's dangerous. tell us more about this bureau 121. >> reporter: it's all too real, carol. i was in north korea a few months ago and i can tell you how remarkable it is that this country is able to pull together the funds to train and supply this group of 1800 technical wizards plugged from the elite. they can barely scrape together enough food and even in that capital city where they don't have enough electricity to keep the lights on 24 hours, they somehow manage to keep this group fully powered and fully supplied so that they can basically conduct these cyberattacks. this is the first kind of attack they've conducted on the united states but they've credited south korean broadcasters with this similar tactic. with the u.s. being affected,