'Stand your butt up': GOP senator challenges union boss to fist fight — and Bernie Sanders is forced to break it up

A fight nearly erupted at a Senate hearing on Tuesday between Sen. Markwayne Mullin (R-Okla.) and a Teamsters union boss, forcing Sen. Bernie Sanders (I-Vt.) to step in and calm tempers.

In June, Teamsters general president Sean O'Brien personally attacked Mullin and appeared to challenge him to a fight following a tense exchange at a hearing in March.

"Greedy CEO who pretends like he's self made. In reality, just a clown & fraud. Always has been, always will be," O'Brien said. "Quit the tough guy act in these senate hearings. You know where to find me. Anyplace, Anytime cowboy."

Mullin responded by challenging O'Brien to an MMA-style fight, but nothing ever happened.

That all changed on Tuesday when Mullin confronted O'Brien about his social media threat during a Senate Committee on Health, Education, Labor, and Pensions hearing.

Mullin read the social media post into the congressional record, and then he offered to throw down.

"Sir, this is a time, this is a place. You want to run your mouth. We can be two consenting adults. We can finish it here," Mullin said.

"OK, that's fine. Perfect," O'Brien responded.

"You wanna do it right now?" Mullin asked.

"I'd love to do it right now," O'Brien said.

"Well, stand your butt up then," Mullin shot back.

"You stand your butt up," O'Brien told Mullin.

And that's exactly what the Republican senator did. He jumped up from his seat, stuck out his chest, and appeared ready to fight O'Brien. But Sanders, the committee chairman, would not allow it.

"No, no. Hold it. Stop it. Sit down. Sit down. You're a United States senator. Sit down," Sanders reprimanded.

Mullin and O'Brien continued to trade personal barbs over the next several minutes — Mullin called O'Brien a "thug" while O'Brien called Mullin a "12-year-old schoolyard bully" — before Sanders finally regained control of the hearing.

After the hearing, Mullin defended his conduct.

"He called me out," Mullin said. "He said 'anytime, anyplace.' You don't call me out and say 'anytime, anyplace' and then not back it up what you said. ... I'm still a guy. He called me. He said it. I just answered the bell. That was all."

Mullin, according to his Senate website, is a "former undefeated Mixed Martial Arts (MMA) fighter with a professional record of 5-0."

SHOCKING: Markwayne Mullin Actually Challenges Dem Witness To A Fight, Then All Hell Breaks Loosewww.youtube.com

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