The King and Queen Consort have been targeted by a lone protestor who threw eggs at them, yelling that the country was built on the blood of slavery.
The protestor was standing in the crowd at Micklegate Bar, in York, where the royal couple were due to be officially welcomed to the city.
The man was heard to shout “this country was built on the blood of slaves” as he was being detained by around four police officers.
As he was bundled to the ground by police, onlookers chanted “shame on you” and “God save the King”.
The eggs came within around a foot of the King, who was greeting wellwishers waiting to meet him.
As the attack began, a chorus of boos rang out from the crowd.
The King looked down and appeared to notice the eggs on the ground around his feet but ignored them and tried to carry on shaking hands.
However, one of his protection staff gestured that they needed to move on by touching his shoulder.
The royals were quickly ushered away.
Charles and Camilla are visiting Yorkshire to carry out a number of engagements today.
They were in York to attend the unveiling of a statue of Queen Elizabeth II, the first to be installed since her death.
It is not the first time the monarch has been targeted.
In Riga, Latvia, in 2001 he was attacked by a schoolgirl who was protesting against the war. He was struck across the cheek with the stem of a rose during a walkabout.
Alina Lebedyver, 16, was later charged with endangering the life of a foreign dignitary.
In January 1994, protester David Kang, 23, fired two blank shots at the then Prince Charles during an Australia Day speech at Tumbalong Park, Darling Harbour in Sydney.
The late Queen and Duke of Edinburgh were pelted with eggs during a visit to Dresden, Germany, in 1992.
The city authorities had been keen for the Queen to lay a wreath at the Frauenkirche, whose ruins stand in the centre of Dresden, while locals wanted an apology for the firestorm that destroyed the city after an RAF raid in February 1945.
However, royal historian Hugo Vickers said the Queen did not let the incident affect her and that she “carried it off well” when she visited the city’s Kreuzkirche church.
She was also booed by a strong crowd of 5000 people as she was entering the church.