The statement notes that they began "spearphishing" volunteers and employees of Clinton's campaign, including its chairman.
Deputy Attorney General Rod Rosenstein made the announcement, as Attorney General Jeff Session has recused himself from any investigations into Russian interference, having been an advocate of Trump during the campaign. They used a scheme known as "spearfishing" which tricked users into disclosing their information that allowed hackers to gain access to emails.
Special Counsel Robert Mueller's inquiry is looking into alleged Russian Federation meddling in the 2016 election.
Rosenstein said that responsibility for this prosecution - which is unlikely to go forward in court as Russian Federation is unlikely to extradite the suspects - would pass from Mueller's office to the National Security division of the Justice Department.
To date, Mueller's probe has netted five guilty pleas, including from Trump's ex-national security adviser, Michael Flynn, along with almost 32 indictments, including the president's former campaign chairman, Paul Manafort.
"In my remarks, I have not identified the victims", Rosenstein said. Fourteen of those charged are Russians who are unlikely to ever be put on trial in the United States.
"There is no allegation in this indictment that Americans knew they were corresponding with Russian intelligence officers", said Rosenstein, who also noted there is no evidence the alleged hacking had any impact on the election results. Our response must not depend on who was victimized,"Rosenstein said".
The U.S. intelligence community has concluded, with further verification by the Senate intelligence committee, that Russia's active measures were aimed at hurting Clinton and helping Trump.
President Trump told reporters a few few hours before Rosenstein spoke that he plans to bring up Russia's election interference campaign Monday with President Vladimir Putin when they meet in Helsinki, Finland.
Trump said at a news conference Friday near London with British Prime Minister Theresa May that he wasn't going into the meeting with Putin with "high expectations".
What Melania Trump will be doing in London
Speaking on ITV's Good Morning Britain today, Ms Thornberry said it is "extraordinarily rude of Donald Trump to behave like this". White House spokeswoman Sarah Sanders later told reporters Trump was "thankful for the wonderful welcome" he received in Britain.