King Charles and Queen Consort Camilla were greeting fans in York on Wednesday, November 9, when they were hit with eggs by a protestor.
According to reports, a 23-year-old man threw the food at the pair as he shouted, "This country was built on the blood of slaves!"
Four police officers grabbed the suspect, and Charles and Camilla carried on with their duties for the day.
The young man has since been arrested on "suspicion of a public order offense."
Charles was in town to unveil a statue of his late mother, Queen Elizabeth, who died in September.
"The creation of this statue is also a tribute to the support, affection and prayers that the community of this cathedral, and of this great city, always gave the late Queen," a message on the royal family's Instagram page said. "And all for which she stood in the life of the nation and the Commonwealth."
After the Queen died at 96 years old, King Charles paid tribute to the monarch.
"Her dedication and devotion as Sovereign never waivered, through times of change and progress, through times of joy and celebration, and through times of sadness and loss," he said in a speech.
"In 1947, on her twenty-first birthday, she pledged in a broadcast from Cape Town to the Commonwealth to devote her life, whether it be short or long, to the service of her peoples. That was more than a promise: it was a profound personal commitment which defined her whole life," he continued. "She made sacrifices for duty. Her dedication and devotion as Sovereign never waivered, through times of change and progress, through times of joy and celebration, and through times of sadness and loss."
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