U.S. Special Counsel Robert Mueller's office says hackers in Russia stole and altered evidence in an attempt to discredit its probe into Russia's efforts to interfere in the 2016 U.S. presidential election.

In a filing in Washington released on January 30, prosecutors said a Twitter account named @HackingRedstone came online on October 22 to brag it had hacked some of the evidence in the case of a firm charged with funding a Russian propaganda campaign to meddle in the election.

Russia denies interfering in the U.S. election, and Foreign Ministry spokeswoman Maria Zakharova on January 31 called the latest allegations "a little absurd."

Mueller's office said the Twitter account purported to have a stolen copy of evidence provided to the company, Concord Management and Consulting LLC.

"We've got access to the Special Counsel Mueller's probe database as we hacked Russian server with info from the Russian troll case," the court document quoted the Twitter post as saying.

The data the account published online was "altered and disseminated as part of a disinformation campaign aimed [apparently] at discrediting ongoing investigations into Russian interference in the U.S. political system," prosecutors said in the filing.

Concord was one of three entities and 13 individuals charged in February 2018 by Mueller as part of a conspiracy to spread disinformation on social media during the 2016 presidential campaign.

Companies listed on the indictment included the Internet Research Agency, known for its "trolling" on social media; Concord Management and Consulting LLC, which is alleged to have provided financial backing for the operation; and Concord Catering.

Based on reporting by Reuters and AP