WASHINGTON – There's a strange new twist in the case against a Russian internet company federal prosecutors say helped carry out a disinformation campaign to sway the 2016 presidential election.

Prosecutors said Wednesday that documents special counsel Robert Mueller provided to the company's lawyers had been "altered and disseminated as part of a disinformation campaign," this time aimed at discrediting the investigation of Russian election interference. That led the FBI to investigate a disinformation campaign about the investigation of the Russian disinformation campaign.

Mueller's office said in a court filing that the FBI had determined their computers had not been hacked. Instead, they said documents posted illegitimately on the web had been provided to one of the defendants in the case, Concord Management and Consulting, LLC.

The prosecutors said the incident was “intended to discredit the investigation in this case” and with documents that were subject to a court order meant to limit their disclosure.

The twist came as prosecutors and lawyers for Concord spar over whether people who work for the Russian company should be allowed to see some of the evidence the government has gathered against the firm. Prosecutors urged U.S. District Judge Dabney Friedrich not to force sharing sensitive documents with the defense team because sending sensitive documents "to the Russian Federation unreasonably risks national security interests of the United States."

Lawyers for Concord Management didn’t immediately respond to a request for comment.

They had protested that it was unfair for prosecutors to limit how much information they could share with their client. "Could the manner in which (Mueller) collected a nude selfie really threaten the national security of the United States?" they said in a court filing last year.

The case began in February 2018, when a federal grand jury indicted 13 Russian nationals and three Russian entities including Concord Management with conspiracy to defraud the United States. The defendants allegedly created false personas and social-media pages to influence the 2016 election.

Defense lawyers requested access to sensitive prosecution documents Dec. 20, in order to prepare for trial. The lawyers characterized the case as a “make-believe crime” and said Russian defendants deserved the same access to documents as Americans.

But prosecutors described in their Wednesday filing how a new Twitter account boasted on Oct. 22 that it had hacked into Mueller’s database and was offering access to documents about the case.

“We’ve got access to the Special Counsel Mueller’s probe database as we hacked Russian server with info from the Russian troll case Concord LLC v. Mueller,” the tweet said. “Enjoy the reading!”

The FBI found no evidence that hackers intruded on Mueller’s computers. But the FBI reviewed 300,000 files on the web portal linked from the tweet, posted by a now-suspended account with the name "HackingRedstone," and found that the files and folders were similar to those prosecutors had provided to Concord Management’s defense lawyers. The documents included information about search warrants and contained tracking numbers used by the special counsel.

Concord Management lawyers told prosecutors the next day that the documents could have been hacked from the company’s computers in 2014.

But prosecutors rejected the explanation, saying the documents carried the same names and folders as the current case, which began in February 2018.

"The use of the file names and file structure of the discovery to create a webpage intended to discredit the investigation in this case described above shows that the discovery was reproduced for a purpose other than the defense of this case," prosecutors said in the 18-page filing.

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