King Charles' brother, Andrew Mountbatten-Windsor, 66, arrested on his birthday over alleged misconduct in public office

Andrew Mountbatten-Windsor, the former United Kingdom prince and King Charles' younger brother, was arrested on Feb. 19 over alleged public office misconduct.

According to BBC, he was arrested at a property on the Sandringham Estate in Norfolk at around 8am (UK time).

King Charles said in a statement on the same day that "the law must take its course", reported The Guardian.

Police continue searching homes

Police searches at two properties, including Andrew's former residence at Royal Lodge in Windsor, were carried out.

Thames Valley Police officers were seen stationed at the gates of the estate, while members of the press were held back at an outer entrance.

However, the area surrounding Windsor Great Park remains open to the public.

"The law must take its course": King Charles

According to The Guardian, King Charles and Buckingham Palace were not informed in advance of Andrew's arrest.

In a statement, King Charles said he has "learned with the deepest concern" about his arrest and alleged misconduct in public office.

He added: "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."

King Charles said the UK authorities have the royal family's "full and wholehearted support and co-operation".

"The law must take its course. As this process continues, it would not be right for me to comment further on this matter," he noted, adding that the family will continue in their duty and service to citizens in the meantime.

Andrew remains in custody, location unknown

Andrew, who turned 66 on Feb. 19, had previously denied any wrongdoing after being associated with convicted financier Jeffrey Epstein.

He had allegedly shared official documents, including summaries from trade visits, a confidential briefing on an Afghanistan investment, and passed a Treasury document to a personal business associate.

However, investigators have not released details about the case that resulted in his arrest.

BBC reported that Andrew remains in custody but the location of his detention has not been disclosed.

His royal status will also have no bearing on how the case is evaluated under the law.

Top photos via The Royal Family/Facebook & Epstein Files