BRITAIN’S scandal-ridden monarchy was handed a historic humiliation today with the arrest of Andrew Mountbatten-Windsor on suspicion of misconduct in public office.

Pressure mounted on King Charles and his heir Prince William to come clean on what they knew about Mountbatten-Windsor’s shady activities.

Police swooped on the former prince at his new home on the King’s private Sandringham estate in Norfolk and took him into custody.

He was held in a police custody suite prior to interview as he marked his 66th birthday.

Police are probing the apparent leaking of documents by the then-Prince Andrew when he was Britain’s official trade envoy.

The recently released Epstein files show that the late paedophile financier, once an intimate friend of the prince, was apparently given secret government reports on economic opportunities by Mr Mountbatten-Windsor.

Thames Valley Police, which is leading the investigation, said: “We have today arrested a man in his sixties from Norfolk on suspicion of misconduct in public office and are carrying out searches at addresses in Berkshire and Norfolk.

“The man remains in police custody at this time.”

The force’s assistant chief constable Oliver Wright added: “Following a thorough assessment, we have now opened an investigation into this allegation of misconduct in public office.

“It is important that we protect the integrity and objectivity of our investigation as we work with our partners to investigate this alleged offence.

“We understand the significant public interest in this case, and we will provide updates at the appropriate time.”

Mr Mountbatten-Windsor has always denied any wrongdoing in his dealings with Epstein. He is further being investigated for an alleged sex-trafficking offence, which he has also denied.

The arrest was welcomed by the family of the late Virginia Giuffre, who claimed that she was trafficked by Epstein to have sex with Mr Mountbatten-Windsor.  

The latter denied the allegation, but paid Giuffre around $12 million (£8.9m) to settle legal proceedings in the US.

The family said in a statement: “At last, today our broken hearts have been lifted with the news that no-one is above the law — not even royalty.

“On behalf of our sister, we extend our gratitude to the Thames Valley Police in their investigation and arrest of Andrew Mountbatten-Windsor. He was never a prince. For survivors everywhere, Virginia did this for you.”

The police actions follow a reference by anti-monarchy campaign group Republic. The campaign’s founder, Graham Smith, said today: “Make no mistake, this is a result of Republic’s action.

“We reported Andrew to the police when others were unwilling to act. Republic has been instigating a private prosecution when the police were reluctant to investigate.

“Republic’s lawyers will continue to investigate related alleged offences and provide information to the police over the coming weeks and months.

“The police must follow all evidence wherever it leads. In the meantime, Charles and William need to speak up and admit to whatever they have known.”

The King himself said that “the law must take its course” in the case. He said: “I have learned with the deepest concern the news about Andrew Mountbatten-Windsor and suspicion of misconduct in public office.

“What now follows is the full, fair and proper process by which this issue is investigated in the appropriate manner and by the appropriate authorities.

“In this, as I have said before, they have our full and wholehearted support and co-operation.”

Less than half the public still support the retention of the monarchy, according to recent polling, with one-third preferring an elected head of state.

Mr Mountbatten-Windsor was stripped of all his titles by the King last October as the scandal around his association with Epstein deepened.

He was also obliged to leave palatial accommodation in Windsor to move to the smaller premises in Norfolk.

His reputation has been in freefall since 2019, when he gave a disastrous interview to the BBC’s Emily Maitlis. He attempted to clear his name in relation to Epstein but came across as insensitive, entitled and mendacious.

The subsequent release of the Epstein files in the US has underlined that he did not break his links with the paedophile after his conviction on child sex charges, as he had claimed.

Emails in the files appear to show the then-prince sharing reports of official trips around Asia with the financier.

He also apparently forwarded a confidential government briefing on investment opportunities in Afghanistan in 2010, minutes after receiving it.

Transparency International chief executive Daniel Bruce noted: “Misconduct in public office is among the most serious offences in English law.

“Any proven abuse of a senior public role for private ends, financial or otherwise, is corruption that erodes public trust in our institutions.”

Mr Mountbatten-Windsor appears to be the first member of the immediate royal family to be arrested since Charles I in 1648.

Before that royal arrests were more common, with Mary Queen of Scots, Anne Boleyn and the Duke of Clarence among those detained.

None of these precedents are encouraging for the former prince, as their fates differed only in the method of their eventual execution. Mr Mountbatten-Windsor would, however, face a maximum sentence of life imprisonment if convicted.