King Charles has expressed his "deepest concern" and said the "law must take its course" after his brother, Andrew Mountbatten-Windsor, was arrested at his Sandringham home on suspicion of misconduct in public office.

The former royal was arrested by Thames Valley Police this morning after at least six unmarked police cars arrived at Wood Farm, on what is Andrew's 66th birthday.

Thames Valley Police had previously said it was assessing reports that Andrew shared confidential information with the late paedophile financier Jeffrey Epstein.

Emails released in recent weeks by the US Department of Justice appeared to show the former duke sharing reports of official visits with Epstein when he was a UK trade envoy.

In a statement released after Andrew's arrest, the King said: “They [the police] have our full and wholehearted support and co-operation", adding: "Let me state clearly: the law must take its course."

The King added, "it would not be right for me to comment further on this matter," and said he would "continue in our duty and service to you all."

Andrew has consistently denied all claims made against him in relation to Epstein.