British police on Thursday released Andrew Mountbatten-Windsor, the former prince and brother of King Charles III, after having arrested him earlier on suspicion of misconduct in public office.

The nature of the investigation has not been revealed. But Mountbatten-Windsor’s arrest came after renewed focus on his past friendship with Jeffrey Epstein, the now-dead, notorious sex offender, after the U.S. Department of Justice released millions of documents about Epstein.

Thames Valley Police, who had arrested Mountbatten-Windsor without publicly identifying him, had said they were assessing reports that he had sent Epstein confidential trade reports in 2010, when he was Britain’s special envoy for international trade.

Thames Valley Police, in a statement, said, “On Thursday ... we arrested a man in his sixties from Norfolk on suspicion of misconduct in public office.”

“The arrested man has now been released under investigation,” police said. “We can also confirm that our searches in Norfolk have now concluded. Our searches in Berkshire are still underway.”