During a engagement to a cathedral in Staffordshire on Monday, King Charles was shouted at by a protester who asked him about his brother's connections with disgraced financier Epstein.
The man inquired how long the monarch had been known about his brother's relationship with Epstein, and also questioned whether he had instructed the police to "cover up" for Prince Andrew.
Despite the protest, there were large groups of supporters and cheers for the monarch, who was visiting the region for an ceremony.
The Duke of York's associations with Jeffrey Epstein have been under renewed focus in recent weeks. The royal, who relinquished his royal duties earlier this month, has strongly denied any wrongdoing.
"For how long have you been aware about Andrew and Jeffrey Epstein? Did you request the police to cover up for him?"
The monarch did not respond but carried on greeting fans, some of whom chanted "God Save The King". One fan can be overheard requesting him for a hug.
A female bystander outside the venue was also observed telling the protester to "leave" and to "be quiet".
The scandal over the Duke of York's connections to Jeffrey Epstein has been reignited by sexual abuse allegations repeated in Virginia Giuffre's posthumously-published book.
In the memoir, Ms Giuffre alleges she had sexual encounters with the royal on multiple times, including one instance with Epstein and "eight other young girls"
Andrew, who agreed to a financial settlement with Ms Giuffre in 2022, has consistently denied any wrongdoing. In 2019, he told a news program he did not remember meeting Ms Giuffre "at all", and that they "never had any sort of intimate relations."
But recently, new inquiries have been raised about how he is able to finance his lifestyle despite not being a working royal.
The disclosure that he has only ever paid a nominal fee on his Royal Lodge has heightened the examination over his housing situation - even though he made large payments up front, including for improvements.
The political party said he should be summoned before members of parliament to give testimony about his rental agreement of his residence.
But last Thursday, the authorities refused to give parliamentarians time to debate the royal's status or his residence, despite increasing calls for investigation.
The royal household has not commented on whether Prince Andrew might move out of his home - or where he might reside.
Lena Visser is techjournalist met focus op startups en digitale transformatie in Eindhoven.