President Donald Trump's son Eric Trump said an employee of an upscale Chicago cocktail bar spit on him Tuesday night in an incident he believed was politically motivated.

"It was purely a disgusting act by somebody who clearly has emotional problems," the executive vice president of the Trump Organization told Breitbart News.

"For a party that preaches tolerance, this once again demonstrates they have very little civility," he added, apparently assuming the employee was a Democrat. "When somebody is sick enough to resort to spitting on someone, it just emphasizes a sickness and desperation and the fact that we’re winning."

The incident reportedly occurred at The Aviary, a James Beard award-winning establishment co-owned by Nick Kokonas.

Kokonas made headlines earlier this year when he invited Clemson University's NCAA championship football team to "experience what an actual celebration dinner should be" after the team was given fast food during a trip to the White House, where the staff had been impacted by a government shutdown.

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Mary Ann Ahern, a reporter for NBC5 in Chicago, first reported the incident and said Trump was seen leaving The Aviary at 8:30 p.m., CDT. Ahern said the employee had been taken into custody.

A Chicago Police Department spokesman, linking to a tweet from Ahern, said that local officers had assisted the Secret Service "with a law enforcement matter" but did not provide further details.

The alleged spitting is the latest in a string of incidents in the past two years in which members of the Trump administration, as well as Republican lawmakers, have described being confronted and harassed at restaurants by people over policy differences.

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In June 2018, White House Press Secretary Sarah Sanders was asked to leave a Virginia restaurant. That same month, then-Homeland Security Secretary Kirstjen Nielsen was confronted at a Mexican restaurant in Washington by protesters who were enraged at the administration's child separation policy.

Stephen Miller, one of the chief architects and advocates of the White House's "zero tolerance" immigration policies, has been a prime target for the administration's critics.

Last year, Miller told The Washington Post that he threw away an $80 sushi order after the restaurant's bartender followed him out with both middle fingers raised. And in June, a fellow patron at a Washington Mexican restaurant called him a "fascist," according to the New York Post.

Eric Trump posted a tweet later Tuesday night touting the Trump Hotel in Chicago as "one of the most beautiful buildings in the world," but did not mention the alleged incident.