A heckler shouted an apparent reference to the Jeffrey Epstein affair at the King and Queen during a high street walkabout.
Charles and Camilla held umbrellas as they walked in the Essex village of Dedham in the drizzle, with crowds gathered behind metal barriers to meet them.
A man in the crowd, who was wearing a grey hat and holding a blue umbrella, shouted as the King was near him: “Charles, Charles, have you pressurised the police to start investigating Andrew?”
Police officers approached the man afterwards and walked with him away from the barriers.
Shortly afterwards a news reporter in the crowd – who was beside a cameraman – apparently tried to ask Charles a question about his brother.
The King was then led to the far side of the road, away from the crowds, to continue the walkabout.
Charles and Camilla had earlier met local groups inside the Sun Inn pub and went into the kitchen where Camilla tried her hand at cutting ravioli pasta.
Towards the end of their walkabout they listened to a choir of schoolchildren in the street, before briefly going into the Essex Rose Teahouse where Charles unveiled a plaque and cut a cake.
After going back outside they spoke to more members of the public before leaving in a Bentley.
Adrian Sharpe, of Dedham, was among the crowds who turned out to see the King and Queen.
The 62-year-old handyman said it was “nice and casual really for a village event – obviously high security”.
Asked about the heckler, he said: “I think it’s pointless really as what Andrew’s done is what Andrew’s done, it’s not what King Charles has done is it?
“He’s his own person.”
He said that “they’ve taken the HRH off of Andrew”, adding: “What else can they do?
“Surely it’s a police matter now.”
Retired health and safety consultant Russell Townsend, of Stratford St Mary, was also in the crowd.
“We shook the Queen’s hand but the King went across the road so we only saw the back of him really,” he said.
Asked about the situation with Andrew Mountbatten-Windsor, the 67-year-old said: “I must admit today I didn’t think of it really.
“I kind of see it as quite a separate issue really.
“I just think it is what it is and I can kind of separate the two.”
Mr Townsend’s daughter Phoebe, 22, said: “I don’t really follow that.
“I’m just here to see the King.
“If it was Prince Andrew maybe not, but the King’s the King.”
Photographs of Andrew released in the so-called Epstein files appeared to have been scattered around Dedham ahead of Thursday’s visit by the King, the East Anglian Daily Times reported.
The image was included as part of the latest batch of files released by the US Department of Justice relating to the late paedophile financier Jeffrey Epstein.
A video of the scattered printouts of the image was posted on social media on Wednesday.
Andrew, who moved from Royal Lodge, his Windsor mansion, to the King’s Sandringham Estate on Tuesday, has previously strongly denied any wrongdoing.
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