U.K. police have arrested Andrew Mountbatten-Windsor on suspicion of misconduct in public office.
On Thursday, Thames Valley Police said they opened an investigation after assessing reports about his alleged contact with Jeffrey Epstein.
Police did not name him.
That follows U.K. practice, but they confirmed they arrested a man in his 60s.
Mountbatten-Windsor has repeatedly denied any wrongdoing in his relationship with Epstein.
He is the former Prince Andrew.