A federal grand jury on Friday indicted the Russian intelligence officers on charges of hacking the computer networks of 2016 Democratic presidential candidate Hillary Clinton and the Democratic Party, he said.
U.S. intelligence agencies have said the interference was aimed at helping the presidential campaign of Republican Donald Trump and harming the election bid of his Democratic opponent, Hillary Clinton.
All 12 intelligence officers are members of the GRU, Russia’s main intelligence agency.
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Rosenstein said the intelligence officers allegedly hacked the state election boards and stole information of about 500,000 voters. He added that the indictments include money laundering through cryptocurrency.
The effort also included bogus Facebook ads and social media postings that prosecutors say were aimed at influencing public opinion and sowing discord on hot-button social issues.
“The internet allows foreign adversaries to attack Americans in new and unexpected ways,” Rosenstein said.
“Free and fair elections are hard-fought and contentious and there will always be adversaries who work to exacerbate domestic differences and try to confuse, divide and conquer us.”
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The deputy attorney general said there are no allegations that Americans were involved in the hacking, or that any vote counts were altered.
The fresh indictments related to special counsel Robert Mueller‘s probe come amid Trump’s U.K. visit, and just hours after he once again called the investigation a “witch hunt.”
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Rosenstein said the president had been briefed on the charges earlier this week.
Trump is scheduled to meet Russian President Vladimir Putin on Monday in Finland.
The Kremlin denied meddling allegations once again Friday, after news of the indictments broke.
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“The Russian state has never interfered and has no intention of interfering in the U.S. elections,” said Putin’s foreign affairs adviser, Yuri Ushakov.
Twenty people and three companies had already been charged in the investigation prior to Friday’s announcement.
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— With files from The Associated Press, Reuters