View from the entry plaza at the United States Institute of Peace. (Timothy Hursley/Courtesy Safdie Architects)

For an event held at the soaring U.S. Institute of Peace building in Foggy Bottom, the swanky afterparty hosted by MSNBC following the White House Correspondents’ Association dinner sure saw some conflict.

In the early-morning hours of Sunday, a scuffle broke out between Fox News correspondent Jesse Watters and Ryan Grim, the Huffington Post’s Washington bureau chief. The fight — unusual among a tuxedo-clad crowd more used to venting their differences with Twitter snarks — briefly caused ripples in the party, where political staffers and journalists were grooving to tunes spun by DJ Biz Markie and noshing on mini servings of chili cheese fries.

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Here’s how it went down, per several witness: Grim and Watters were among a group located in a heated tent just outside the main party area. The two apparently don’t have a personal relationship, but Grim realized who Watters was and recalled a beef he had with the “O’Reilly Factor” correspondent that dated back to 2009, when Watters, known as an “ambush journalist,” had engineered an on-camera confrontation of writer Amanda Terkel, now a HuffPo colleague of Grim. Terkel’s account of the incident was headlined “I Was Followed, Harassed, And Ambushed By Bill O’Reilly’s Producer.”

Grim decided to give Watters a taste of his own medicine, whipping out his camera phone and filming him. Watters didn’t take well to this, eventually snatching the phone away from Grim and putting it in his pocket. Grim set out to retrieve it, and a scuffle ensued. No cinematic sparring or broken beer bottles, witnesses said, but the two flailed around a bit, upending a table and bumping into several people.

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“Punches were definitely thrown,” said one witness.

Before any damage was done, several bystanders, including Sean Spicer, communications director at the Republican National Committee, separated the two. Spicer said he didn’t see the lead-up to the fight and said he was merely attempting to stay true to the party venue. “Just trying to keep the peace,” he said.

Asked for comment, a Fox spokeswoman said the most Washington thing ever: “Jesse will address the issue tomorrow night on The O’Reilly Factor.” Meanwhile, Grim was unrepentant. “Ambush guy can’t take getting ambushed,” he said. “Maybe he should think about his life choices.”

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