Separately, The Daily Beast reported that Mueller's team has determined that the person calling himself Guccifer 2.0, who leaked sensitive DNC documents in the months leading to the 2016 election, is a Russian intelligence officer.
A grand jury in the special counsel probe has returned the indictment of 12 Russian intelligence officers for hacking during the 2016 election - including hacking emails of the Democratic National Committee, Deputy Attorney General Rod Rosenstein announced Friday.
Additionally, former National Security Adviser Michael Flynn and Trump campaign adviser George Papadopoulos have pleaded guilty to making false statements to the Federal Bureau of Investigation about the contacts they had during the campaign with Russians.
The indictments were announced Friday by Deputy Attorney General Rod Rosenstein as part of the ongoing special counsel probe into potential coordination between the Trump campaign and Russian Federation. They also hacked into networks and installed malicious software that captured keystrokes, took screenshots, and allowed them to take data from the computers.
The hackers, the DOJ said in its press release, released the hacked information "on the internet under the names DCLeaks and Guccifer 2.0 and through another entity".
It comes days before Mr Trump's Helsinki meeting with Russian President Vladimir Putin, casting a major shadow over the encounter.
The unfolding drama on both sides of the Atlantic reflected how Trump's presidency has been overshadowed by the Mueller probe from its earliest moments and how the investigation frequently tramples the President's attempts to carve out favorable headlines.
The Russia investigation has now led to charges against 32 people, including previous charges against 14 Russian nationals for their work on spreading Russian-based propaganda.
The charges were brought as part of special counsel Robert Mueller's investigation into whether there was any collusion between Donald Trump's campaign and Russian Federation. The current indictment did not allege that any Americans committed crimes related to the Russian hacking, Rosenstein announced.
"He needs to know what evidence there is of foreign election interference", said Rosenstein.