Andrew Mountbatten-Windsor, the former Prince Andrew, was reportedly treated like a "common criminal" during the 11 hours he was in police custody on Thursday (February 19), the Sun reports.

Mountbatten-Windsor, the younger brother of King Charles, reportedly planned to spend his 66th birthday at home with his seven dogs when he was arrested by Thames Valley Police on suspicion of misconduct in public office for allegedly passing secret documents to late convicted pedophile Jeffrey Epstein. The former prince took DNA swabs, fingerprints and a mugshot while detained, the Sun reports.

“I doubt whether the police gave him tea in a bone china cup and the microwaved food in custody centres is virtually inedible,” said Mick Neville, a retired detective chief inspector. “It’s an extraordinary fall from grace.”

Investigators combed Mountbatten-Windsor's Sandringham home and his former Royal Lodge and he was released 11 hours later. An apparent police presence was shown in photos captured from Wood Farm on the Sandringham estate in eastern England Thursday.

King Charles issued a statement confirming he was aware of his brother's arrest.

"I have learned with the deepest concern the news about Andrew Mountbatten-Windsor and suspicion of misconduct in public office," he said via ABC News.

"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," Charles added."Let me state clearly: the law must take its course. As this process continues, it would not be right for me to comment further on this matter. Meanwhile, my family and I will continue in our duty and service to you all."

Mountbatten-Windsor's arrest followed more documents detailing past communication between him and Epstein, which date back to 2010, being released recently including the late convicted pedophile's correspondence with David Stern, Mountbatten-Windsor's aide, suggesting the latter may have planned to use his role as a special United Kingdom representative for trade and investment for his personal business interests. Mountbatten-Windsor was stripped of his title and forced to move out of his Royal Lodge home, Buckingham Palace announced in a statement released on October 30.

"His Majesty has today initiated a formal process to remove the Style, Titles and Honours of Prince Andrew," the palace said. "Prince Andrew will now be known as Andrew Mountbatten-Windsor. His lease on Royal Lodge has, to date, provided him with legal protection to continue his residence. Formal notice has now been served to surrender the lease and he will move to alternative private accommodation. These censures are deemed necessary, notwithstanding the fact that he continues to deny the allegations against him.

"Their Majesties wish to make clear that their thoughts and utmost sympathies have been, and will remain with, the victims and survivors of any and all forms of abuse."

Mountbatten-Windsor had previously announced that he would immediately stop using titles and honors, including the Duke of York, in a statement released on October 17. The disgraced royal initially stepped back from his public duties in 2019 and later royal patronages in January 2022 after his lawyers failed to have a lawsuit by Virginia Giuffre accusing him of sexual abuse dismissed.

Mountbatten-Windsor later paid Giuffre, who claimed the alleged sexual abuse took place when she was 17 and later reported to have died by suicide at the age of 41, a substantial sum, but has repeatedly denied the allegation publicly.