SANDRINGHAM, United Kingdom: Former prince Andrew hunkered down Friday at home on the king’s private estate after hours of police questioning, as his stunning arrest tipped the British monarchy into an unprecedented crisis in its modern era.

The disgraced royal was “released under investigation” late Thursday, with police believed to be continuing Friday searches of his former home on the royals’ Windsor estate, west of London.

In a sensational development in investigations into his links to the late US sex offender Jeffrey Epstein, Andrew spent around 11 hours in custody after police arrested him on suspicion of misconduct.

Officers swooped early Thursday on his home in Sandringham, eastern England, taking him into custody at a nearby police station while also raiding his former Windsor home.

It prompted the king to swiftly issue a rare personally signed statement insisting “the law must take its course,” as he reiterated Buckingham Palace would support the police probe.