Andrew Mountbatten-Windsor has been released following his arrest on suspicion of misconduct in public office.
Thames Valley Police earlier said they were looking at allegations that Mountbatten-Windsor had passed confidential government documents to the late sex offender Jeffrey Epstein, according to recently released files.
Mountbatten-Windsor has denied any wrongdoing and said he regrets his friendship with Epstein, but he has not responded to specific requests for comment after the latest files were published by the US government.
King Charles in a statement says that the law must take its course.
Source: BBC