The evidence in the case against Russian company Concord Management, which is accused to have interfered in the 2016 presidential elections, has been "altered and disseminated" after it was given to the firm's defence team during discovery, Special Counsel Robert Mueller's office said on Wednesday.

Discovery is the process through which the prosecution and the defence share evidence with each other in a case.

The US Justice Department had said last year that it had indicted 13 Russian nationals and three entities, one of which were Concord Management and Consulting LLC, for alleged meddling in the 2016 elections, Sputnik reported.

Russia has dismissed all such charges.

Concord's legal team has attempted to appeal the charges several times, however, all their motions have thus far been dismissed.

In a court filing on Wednesday, Mueller said that the US' national security interests would be jeopardised if Concord is allowed to share the sensitive evidence in the criminal case with Russia.

"Concord's request to send the sensitive discovery to the Russian Federation unreasonably risks the national security interests of the United States," Mueller said in the document which was filed at the US District Court for the District of Columbia.

Mueller indicted Concord Management, among others, as part of his investigation into the alleged election meddling. His investigation is also probing allegations that President Donald Trump's campaign colluded with Russia to impact the voting.

Russian officials have refuted all meddling allegations, calling them groundless and invented as an excuse for the loss of Democratic candidate Hillary Clinton.

Trump has also denied any connection between his campaign and Russia, calling Mueller's probe a "witch-hunt" that has produced no evidence thus far.

Acting US Attorney General Matthew Whitaker on Monday confirmed that Mueller's investigation is close to completion.

(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)