Andrew Mountbatten-Windsor, formerly known as Prince Andrew, was arrested Thursday by Thames Valley Police on suspicion of misconduct in public office, marking an extraordinary development for the British monarchy. Authorities confirmed that a man in his 60s from Norfolk was taken into custody and remained detained, though police did not formally name him in accordance with standard U.K. procedure.

The investigation follows reports that Mountbatten-Windsor allegedly sent confidential trade information to convicted sex offender Jeffrey Epstein in 2010 while serving as Britain’s special envoy for international trade. The allegations stem from correspondence included in millions of pages of U.S. Justice Department documents released last month.

Assistant Chief Constable Oliver Wright said police opened the inquiry after a “thorough assessment” of the material. Officers also searched two properties, including Wood Farm on the Sandringham Estate in Norfolk, where Mountbatten-Windsor has been residing after vacating his longtime home near Windsor Castle.

The arrest comes after years of scrutiny surrounding his relationship with Epstein, who pleaded guilty in 2008 to soliciting a minor for prostitution and was arrested again in 2019 on federal sex trafficking charges before dying in custody. Mountbatten-Windsor has consistently denied wrongdoing.

Charles III addressed the situation directly, stating, “Let me state clearly: the law must take its course.” In a written statement signed “Charles R.,” the monarch said it would be inappropriate to comment further while the investigation is ongoing, but emphasized that the royal family would offer its “full and wholehearted support and co-operation” to authorities.

Legal analysts note that suspects in the U.K. are typically held between 12 and 24 hours before being charged or released pending further inquiry, with a maximum detention period of 96 hours requiring judicial approval.

Mountbatten-Windsor previously stepped back from royal duties in 2019 after a widely criticized interview regarding his ties to Epstein. In recent years, he was stripped of military affiliations and royal patronages as public pressure mounted.

The arrest of a monarch’s sibling on suspicion of criminal misconduct is unprecedented in modern British history and places renewed strain on the institution as investigators determine next steps.