Transcript for Cyber Investigators Point Fingers at Russia for DNC Hack
Sanders supporters here are fueled. By what they read in those hacked emails 20000 emails. And tonight US authorities say Russian hackers were behind it on the eve of the Democratic Convention. The question now did Vladimir Putin know. And team Clinton is asking is potent helping Donald Trump ABC's chief investigative correspondent I cross tonight. Tonight as the FBI investigates cyber security experts are blaming in the hack attack on the intelligence agencies Russian president Vladimir Putin. A former KGB colonel himself. This absolutely was not an amateur operation. Security experts say the malware blog. Planted inside the democratic computer contains several telltale signs it was made in Russia including the keyboard that hackers used. It would is in in a Russian. Alphabet if you will that was. Used to create the Bauer. The timing of the release of the 20000 selected emails was clearly designed to disrupt the convention. The supposedly neutral DNC officials discuss raising the issue of whether birdies Sanders was an atheist. And perhaps plant near the story that Bernie never ever had his act together that his campaign was a mess. It all seems part of the well known Russian cyber ops playbook having already hacked into servers at the White House the Pentagon and the State Department. And Brian Ross with this hearing Phillies well tonight Brian you've talked to your security experts your sources they tell you they believe the Russians were behind this but here's the question. Is this just the beginning. Look good question officials say the hackers went undetected for more than a year there's a lot they still that the shots be made public a right you're going to be following the trail all week long Brian Ross tonight prime thanks.
This transcript has been automatically generated and may not be 100% accurate.