Marius Borg Høiby arrested after allegedly violating restraining order against ex-girlfriend

The son of Norway's Crown Princess has been arrested again after allegedly violating a restraining order and contacting a former girlfriend he admitted assaulting.

Charges against Marius Borg Høiby have also been expanded to include the alleged domestic abuse of two former girlfriends.

The 27-year-old is now facing six years in prison after being accused of making threats against four women.

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Høiby was first arrested on August 4 and charged with causing bodily harm and damaging property during an alleged attack on his girlfriend inside her Oslo apartment.

He later admitted to the allegations and apologised to the royal family in a statement.

Høiby was served with a restraining order, which expires in March next year.

Police said he had violated that order by repeatedly contacting his former partner.

He was arrested again at the weekend at a remote hunting lodge where he was staying with friends, north Oslo.

According to Norwegian magazine Se og Hor, police had to use a battering ram to break down the door.

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Officers moved in after receiving "information that Høiby had contacted a woman who is a victim in the case on several occasions" and the arrest took place to avoid "repetition".

Høiby's lawyer, Øyvind Bratlien told local broadcaster NRK: "In my 17 years as a criminal defence lawyer I have never experienced an arrest based on such a thin factual basis."

He spent the night behind bars but has since been released.

Police also recently expanded their case against Høiby after two former girlfriends, Juliane Snekkestad and Nora Haukland, made allegations against him.

In total, the charges relate to his most recent ex-girlfriend involved in the August 4 attack, Snekkestad, Haukland and threats against a fourth person who has not been named.

Høiby, the son of Crown Princess Mette-Marit from a previous relationship before she married Crown Prince Haakon, their heir to Norway's throne.

Last month, sweeping changes were made to the website belonging to Norway's monarchy after a number of scandals hit the royal family.

Two of its most controversial figures have now been removed from the site under the category listing those who are officially part of the royal family.

That includes Høiby and Princess Märtha Louise, who recently married Shaman Durek Verrett.

The new site appears to reflect a slimmed-down monarchy.

Under the headline 'The Royal House of Norway', the members are listed as: King Harald and Queen Sonja, Crown Prince Haakon, Crown Princess Mette-Marit and Princess Ingrid Alexandra, who is heir after her father.

The page previously featured a photograph showing the now-deleted royals standing on the balcony of the palace celebrating the King's Silver Jubilee in June 2016.