Britain’s former Prince Andrew was arrested on suspicion of misconduct during his time as a trade envoy, as the UK police investigation into allegations emerging from the Jeffrey Epstein files gathered pace.

Unprecedented in Britain’s modern era, the arrest was a new blow for the ousted royal, who marked his 66th birthday on Thursday.

Andrew was stripped of all his titles last year and was forced out of his royal home by his brother, King Charles III.

“We have today, 19 February, arrested a man in his sixties from Norfolk on suspicion of misconduct in public office,” Thames Valley police said in a statement, without naming the suspect, as is common practice in the UK.

Several UK media outlets reported a fleet of unmarked cars, believed to be police vehicles, arriving early Thursday at the Sandringham estate in eastern England where Andrew now resides.

New revelations last week appeared to show that Andrew sent convicted US sex offender Epstein potentially confidential documents during his time as a UK trade envoy.

In a November 2010 email seen by AFP, Andrew appeared to share with Epstein reports on Vietnam, Hong Kong, Shenzhen and Singapore following an official visit to Asia.

Epstein connection

The ex-royal, now known as Andrew Mountbatten-Windsor, also reportedly sent the late American financier details of his trip — on which he was accompanied by Epstein’s business associates — along with investment opportunities months later.

The former prince was eventually stripped of his titles after one of Epstein’s victims alleged, she had been trafficked to have sex with him. He had previously denied any wrongdoing in his associations with Epstein.

King Charles has voiced “concern” over his brother’s actions and last week issued an unprecedented statement saying that Buckingham Palace was “ready to support” the police in their inquiries.

Official guidance stipulates that trade envoys have a duty of confidentiality over sensitive, commercial and political information related to their official visits, the BBC said.

Andrew, whose ties to Epstein have caused a spectacular years-long fall from grace, served as a British trade ambassador for a decade from 2001.

At least nine separate UK police forces have confirmed they are assessing reports which appear to link the former prince to Epstein.

Police in Surrey, southeastern England, said Wednesday they had become “aware” of a redacted report alleging “human trafficking and sexual assaults on a minor” between 1994 and 1996 in the village of Virginia Water.