TODAY | October 13, 2012
>>> now to what we're being told is a looming threat against the united states from iran . not a nuclear weapon, but a cyber attack . the secretary of defense says it could create havoc across the country. more now from nbc's pentagon correspondent.
>> reporter: it's predicted that cyber space will become the world's next major battlefield, but in a national call to arms , defense secretary leon panetta warns the threat of a significant cyber attack against america is already here.
>> the collective result of these kinds of attacks could be a cyber pearl harbor .
>> reporter: panetta warned that cyber attackers have tried to shut down america's critical infrastructure . power, water, transportation, and major financial institutions .
>> such a destructive cyber terrorist attack could virtually paralyze the nation.
>> reporter: while russia and china are prime suspects, for the first time, u.s. officials blame iran for the recent jump in cyber attacks. defense officials tell nbc news iran was behind a recent series of attempts to disable the websites of several major u.s. banks. those attacks failed. but another iranian cyber attack nearly shut down saudi arabia 's state oil company . using a sophisticated virus called shamoon, the iranians destroyed 30,000 computers. experts say this complex attack should be a warning to the u.s.
>> we do not have the proper level of security within the financial sector , the oil and gas sector of any of our critical infrastructures.
>> reporter: officials say if iran poses any threat, the u.s. could launch its own cyber attack to shut down iran 's entire electrical system. pa net that warns, however, the internet is a battlefield filled with many enemies and that the u.s. must do more to combat this growing threat.