A shocking morning for the UK, with Andrew Mountbatten-Windsor being held in custody.
Police have been investigating allegations the former Prince shared confidential information with late sex-offender Jeffrey Epstein.
The BBC understands Police gave advance warning of his arrest to the Home Office – the UK government's internal affairs department.
It says his brother King Charles wasn't told of the arrest in advance, but he's released a statement saying the law must take its course.
UK correspondent Vincent McAviney told Ryan Bridge this marks a huge day.
He says you have to go back about 350 years since a member of the Royal Family was captured in any way.
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