Hackers associated with Russia's military intelligence agency targeted a company with information on United States voting software days before the election and used the data to launch "voter registration-themed" cyberattacks on local government officials, according to a top-secret National Security Agency document that was leaked to The Intercept.

"Russian General Staff Main Intelligence Directorate actors.executed cyber espionage operations against a named USA company in August 2016, evidently to obtain information on elections-related software and hardware solutions", the report states.

A 25-year-old United States government contractor has been charged with mishandling classified information, after authorities say she gave a top-secret National Security Agency document to a news organisation.

One of the four authors who wrote The Intercept's story about the NSA report tweeted that nothing in the report indicated that "the actual voting machines or vote tabulations were compromised" in November's election. The report, dated May 5, 2017, is the most detailed US government account of Russian interference in the election that has yet come to light.

Sources confirmed to NBC News that victor was the person behind the leak of the document.

Russian President Vladimir Putin denied during an interview aired Sunday that his government meddled in the USA election, though he admitted last week that "patriotic" Russian individuals may have acted on their own.

The seven-page complaint against victor, filed in Georgia's Augusta Richmond County earlier today, alleges that victor, a 25-year-old contractor with the security system supplier Pluribus International Corporation, printed out and mailed the classified intelligence report to The Intercept.

The hackers are believed to have then used data from that operation to create a new email account to launch a spear-phishing campaign targeting US local government organizations, the document said.

"Russian intelligence obtained and maintained access to elements of multiple USA state or local electoral boards", the NSA concluded, citing information "that became available in April 2017". For example, former NSA contractor Edward Snowden in 2013 disclosed secret documents to journalists, including The Intercept's Greenwald, that revealed broad USA surveillance programs.

While the criminal complaint doesn't identify the government agency, the news outlet, or the report victor allegedly leaked, it does reveal that the report was published May 5, 2017.

Victor was working as a contractor for Pluribus International, and is accused of having given the document in question to The Intercept. Victor was charged with removing classified material from a government facility and sending it to a news outlet.

Winner's attorney, Titus Nichols, said she has no criminal history and is "a very good person".

FBI special agent Justin Garrick told a federal court that victor - a cross-fit fan who graduated high school in 2011 and was in the US Air Force apparently as a linguist - confessed to reading and printing out the document, despite having no clearance to do so. Investigation into the six people involved in printing that document revealed victor had been in contact with The Intercept around the time it changed hands. In May, she allegedly used that clearance to print and removed a top secret intelligence report from the agency, which she then sent it to an unspecified news outlet.

Victor remains in jail pending a detention hearing later this week, said the lawyer, adding that he expects the government will seek to keep her behind bars pending trial.

The latest revelation come on the heels of the arrest of Reality Leigh Winner, a 25-year-old federal contractor from Augusta, Georgia, The Guardian reported.