The altercation, which took place at Greg Gianforte's campaign headquarters in Bozeman, Montana, took place the night before the state's special election.
The Gallatin County Sheriff's Office said it was conducting an ongoing investigation into "allegations of an assault involving Greg Gianforte," but didn't provide further details.
Ben Jacobs, a political reporter for the Guardian, said he had been asking Gianforte about the Republican healthcare plan when the candidate "body slammed" him and began shouting, "Get the hell out of here."
"He took me to the ground," Jacobs told his paper. "This is the strangest thing that has ever happened to me in reporting on politics."
Greg Gianforte just body slammed me and broke my glasses— Ben Jacobs (@Bencjacobs) May 24, 2017
There was a local TV crew there when Gianforte body slammed me. Audio is posting soon at @GuardianUS— Ben Jacobs (@Bencjacobs) May 24, 2017
The audio file provided by Jacobs backs up his account of the incident.
However, Gianforte's campaign blamed the altercation on Jacobs' "aggressive behavior," and offered a version of events at odds with the audio recording.
"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," the campaign said. "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."
Fox News: Reporter didn't show physical aggression
Late Wednesday, Fox News correspondent Alicia Acuna reported that she and her crew witnessed the incident and saw Gianforte grab Jacobs "by the neck with both hands and slammed him into the ground behind him."
"To be clear, at no point did any of us who witnessed this assault see Jacobs show any form of physical aggression toward Gianforte," Acuna wrote.
Jacobs was transferred to the Bozeman Health Deaconess Hospital where he underwent x-rays on his elbow, according to his account of the story.
Gallatin County Sheriff Brian Gootkin said four witnesses are being interviewed, in addition to Jacobs, in relation to the incident.
Gootkin said he wasn't sure of Gianforte's whereabouts. He said authorities are not releasing the identities of the other witnesses at this time.
The sheriff said detectives have been called in to investigate.
Sheriff's office speaks with Gianforte's attorney
Gianforte's attorney, though not Gianforte himself, has been in contact with the Gallatin County Sheriff's Office, Gootkin said. The sheriff declined to elaborate on the conversation.
"If there is an assault then, yes, of course (bodyslamming) is a crime," Gootkin said. However, the sheriff said an investigation has to take place to get a clear picture of the incident.
"You can run into a million different type of situations where there's two sides to every story and if someone may have pushed someone or something like that, that is why law enforcement has to have as much evidence as possible before deciding to pull the county attorney in and request charges," Gootkin said.
A filing from the Federal Election Commission indicates Gootkin donated $250 to Gianforte's campaign in March. Gootkin could not be immediately reached for comment on the donation.
Will it affect the election?
Supporters of Democratic candidate Rob Quist outside an event at a brewery in Missoula were in disagreement about how much effect the Gianforte incident would have on the race.
"It's close, I think, and this could definitely make a difference," said Charley Carpenter, a Missoula resident. "It should make a difference."
Todd Mowbrey, 67, interjected that it wouldn't make any difference for diehard Republican voters.
In Montana, any resident can vote absentee leading to questions about how much of an impact the late incident will have on the results. Both Republicans and Democrats expect that 7 in 10 voters will have already voted before the polls open tomorrow.
Quist himself said it was not his place to comment, and that he was just focused on the issues that are facing the people of Montana.
Kate Gadbow, who supports Quist, said that she was alarmed by the alleged events, noting that it is "an indication of how he would act under pressure."
She said "the last thing we need is one more guy who flies off the handle."
The Democratic Congressional Campaign Committee said in a statement following the incident that Gianforte should "immediately withdraw his candidacy after his alleged violent assault of an innocent journalist." It also called for House Speaker Paul Ryan to National Republican Campaign Committee to denounce the candidate and apologize.
Gianforte, an engineer and businessman, is running against Quist for the state's lone congressional seat, which was vacated by Republican Ryan Zinke upon his appointment to United States Secretary of the Interior.
Late last month, Jacobs reported that Gianforte had nearly $250,000 in shares in two index funds that had investments in Russian companies which were under U.S. sanctions. The Guardian reported that a Gianforte spokesman said the candidate did not oversee his portfolio daily, but looked at its "overall performance."
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