Republican congressional candidate Greg Gianforte speaks to supporters during a campaign meet and greet at Lambros Real Estate on May 24, 2017 in Missoula, Montana.

Montana GOP candidate Greg Gianforte has been accused of assault after he allegedly "body slammed" a reporter during an interview on the eve of the closely watched special election for Congress.

His campaign disputed the version of the events that led to the confrontation Wednesday night with the reporter for The Guardian.

The alleged assault, which reporter Ben Jacobs claimed broke his glasses, came after Jacobs asked Gianforte about the Congressional Budget Office's score of the Republican health-care bill currently in Congress.

Ben Jacobs: Greg Gianforte just body slammed me and broke my glasses

The confrontation occurred one day before voting in the special election to replace former Rep. Ryan Zinke, President Donald Trump's secretary of the Interior.

The contest, held in a state that Trump won in a lopsided vote, has been surprisingly close, becoming a referendum on Trump policies.

The Gallatin County Sheriff Brian Gootkin said in a statement that after completing an investigation, there was probable cause to issue a citation for misdemeanor assault because the injuries didn't meet the requirements for a felony.

Gootkin said that Gianforte had received the citation on Wednesday evening and was scheduled to appear in court sometime before June 7.

Gootkin also noted that while he contributed $250 to Gianforte's campaign in March, it wasn't relevant to the investigation.

An unidentified person was taken to a hospital, NBC News reported.

In the audio recording published by The Guardian, Gianforte can be heard telling Jacobs that he would talk with him later and to speak to his spokesman. That is followed about one second later by what could be sounds of a struggle.

Gianforte can then be heard yelling, "I'm sick and tired of you guys. The last guy who came in here, you did the same thing. Get the hell out of here."

On the recording, Jacobs then states that Gianforte "body slammed me and broke my glasses."

Ben Jacobs: Listen to me get body slammed in Montana

In a statement, Shane Scanion, a spokesperson for Gianforte's campaign said: "Tonight, as Greg was giving a separate interview in a private office, The Guardian's Ben Jacobs entered the office without permission, aggressively shoved a recorder in Greg's face, and began asking badgering questions."

"Jacobs was asked to leave. After asking Jacobs to lower the recorder, Jacobs declined. Greg then attempted to grab the phone that was pushed in his face. Jacobs grabbed Greg's wrist, and spun away from Greg, pushing them both to the ground. It's unfortunate that this aggressive behavior from a liberal journalist created this scene at our campaign volunteer BBQ."

In the audio recording supplied by the Guardian, only one question was asked and Jacobs was not asked to lower the recorder.

A Fox News reporter, Alicia Acuna, who was in the room with two other Fox News employees for a scheduled interview with Gianforte, said they witnessed the incident.

"Gianforte grabbed Jacobs by the neck with both hands and slammed him into the ground behind him. Faith, Keith and I watched in disbelief as Gianforte then began punching the reporter," Acuna said in a posting on the Fox News website.

"At no point did any of us who witnessed this assault see Jacobs show any form of physical aggression toward Gianforte, who left the area after giving statements to local sheriff's deputies," Acuna said.

BuzzFeed reporter Alexis Levinson, who said on Twitter that she was there, tweeted that she didn't see the incident because it was behind a half-closed door, but she saw Jacobs walk into a room where a local TV crew was setting up to interview Gianforte. She then heard "a giant crash" before Jacobs hit the floor.

She noted that Gianforte then left the event early.

Alexis Levinson: So I was there for this - still am

Gianforte's Democratic opponent, Rob Quist, said he hadn't heard the news and that he was focused on the issues facing Montana.

In a statement posted on Twitter, The Guardian's U.S. editor, Lee Glendinning, said his newspaper was "deeply appalled" by how Jacobs was treated while doing his job.

"We are committed to holding power to account and we stand by Ben and our team of reporters for the questions they ask and the reporting that is produced," Glendinning said.

Last month, Jacobs reported in The Guardian that Gianforte had financial ties to U.S. sanctioned Russian companies, citing the candidate's ownership of around $250,000 of shares in Russian exchange-traded funds as stated in financial disclosures.

The Guardian: Statement from Lee Glendinning, Guardian US editor.

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