Andrew Mountbatten-Windsor has been arrested on suspicion of misconduct in public office.
Thames Valley Police confirmed it had arrested a man in his 60s in Norfolk on Thursday and was carrying out searches at addresses in Berkshire and Norfolk. He remains in custody, it said.
King Charles III said the “law must take its course” in response to Andrew’s arrest, and that the police has his “full and wholehearted support and co-operation”.
Police had previously said they were considering investigating Andrew over allegations relating to his association with the late sex offender Jeffrey Epstein.
They were reviewing allegations Andrew shared confidential material with the disgraced financier, after communications between the two were among files released by the US government.
This is the first time Andrew has been arrested. He has consistently and strenuously denied any wrongdoing.
Thames Valley Police said that, following a “thorough assessment”, a formal investigation had now been opened.
By Anthony Solly
