Transcript for Government contractor under arrest for allegedly leaking top-secret NSA memo to the press

Next to the arrest tonight of a government official after a top-secret document leaked. That arrest of a government C contractor for allegedly leaking that document, an army veteran and a language specialist, tonight she's facing charges. First significant proof that Russia wanted to get to the software found in so many voting booths across this country? Here's ABC's justice correspondent Pierre Thomas tonight. Reporter: Tonight, this 25-year-old air force veteran landing in a federal jail, accused of leaking top-secret information. Any disclosure of classified or sensitive information can clearly threaten our national security. Reporter: Reality Leigh winner, an NSA linguist trained in farsi and pashto, who received an air force commendation medal, is described by family as a patriot. A young woman into fitness, seen here on Facebook discussing yoga instruction and competing in weight-lifting. But tonight, her disclosure stunning. Report about Russian meddling in the 2016 election. Efforts by Russian military intelligence to hack the software of U.S. Companies involved in voting machines and voter registration, as well as cyberattacks on more than 100 local election officials. A key senator saying the extent of the attacks is much broader than reported so far. It's important that the American people understand that the Russian attempts to break into a number of our state voting processes was broad-based. Reporter: Winner faces up to ten years in prison and is the first arrest in the trump administration's promised crackdown on leaks. We're gonna find the leakers. They're gonna pay a big price for leaking. Reporter: According to authorities, winner illegally obtained the classified report on may 9th, printed out a copy and mailed it to an online media group called the intercept, leaving a trail of clues. A scanned copy of the document shared by the media outlet with government officials revealed to investigators it had been folded or creased, suggesting it had been printed and hand-carried out of a secured space. An internal audit at the NSA showed only six people had printed out the report and after examining their computers only Ms. Winner had been in email contact with the intercept. This is amateur hour for not only the leaker, but also the news organization reporter. She now awaits her fate. Pierre, back to what that classified document could reveal, we know this election was decided by less than 100,000 votes in three states, any evidence that any voting machines or election software was compromised on election day in this country? David so far no evidence of that. But the investigations are continuing and sources say, the Russians are still launching cyberattacks and could pose a threat to upcoming elections. Pierre, our thanks to you again. There's still much more ahead on "World news tonight"

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