Eric Trump appears on the "Fox & friends" television program in New York, Jan. 17, 2018. Trump says the U.S. Secret Service took an employee of a Chicago cocktail lounge into custody Tuesday after she spit on him. Chicago police say they assisted the Secret Service at the scene. Credit: Richard Drew | AP

An employee at a high-end Chicago cocktail bar was questioned by the Secret Service on Tuesday evening after allegedly spitting on Eric Trump, according to local media reports and an interview with another worker at the establishment.

The president’s son confirmed the incident to Breitbart News.

“It was purely a disgusting act by somebody who clearly has emotional problems,” Trump, 35, told the conservative site.

The Secret Service declined to comment on the incident. Anthony Guglielmi, a Chicago Police Department spokesman, confirmed on Twitter that local officers assisted the Secret Service at the bar but declined to discuss what happened.

Restaurants and bars have regularly become hostile territory for Trump family, staffers and allies in recent years as the establishments’ owners, workers and customers have harassed or chased out everyone from Sen. Ted Cruz, R-Texas, to White House press secretary Sarah Sanders, sparking debate about what constitutes appropriate political protest, and whether such battles should extend to the dinner table.

Eric Trump attributed the alleged spitting incident to the employee’s politics.

“For a party that preaches tolerance, this once again demonstrates they have very little civility,” Trump told Breitbart, apparently referencing Democrats. “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 took place in Chicago’s West Loop neighborhood at the Aviary, a boundary-pushing establishment that has nabbed a James Beard Award for its bar program. Its co-owner, Nick Kokonas, made headlines in January by offering the Clemson Tigers, college football’s national champions, “an actual celebration dinner” at his restaurant Alinea after President Donald Trump served the players a banquet of fast food at the White House.

Eric Trump, executive vice president of the Trump Organization, was at the Aviary around 8:30 p.m. Tuesday when he was allegedly spit on, reported Mary Ann Ahern of NBC 5 Chicago.

After the bar closed for the night, another worker at the Aviary confirmed the basic details of the incident to The Washington Post, though declined to speak on the record.

Hours after the incident, Eric Trump took to Twitter to post photos of his family’s hotel property along the Chicago River, making no reference to what happened at the Aviary.