Norwegian Royal arrested for rape as Crown Princess’ son Marius Borg Hoiby held by cops in latest shock for family

THE son of Norway's crown princess had been arrested on suspicion of rape.

Marius Borg Hoiby, 27, was detained by police on Monday evening in the latest scandal to rock the royal family.

Hoiby - the son of Norwegian crown princess Mette-Marit - is accused of sexually assaulting "someone who is unconscious or for other reasons unable to resist the act", police said.

He was previously detained in August after allegedly attacking his former girlfriend.

Police arrested Hoiby again in September for violating a restraining order.

Officers then detained Hoiby on Monday evening after fresh information came to light during an ongoing investigation.

Prosecutor Andreas Kruszewski alleges Hoiby sexually assaulted a woman in her 20s in Oslo earlier this year.

Hoiby was in a car with the alleged victim from the August incident. when he was arrested by police shortly after 11pm local time, according to police.

On Tuesday, police also said the suspicions relating to the August incident now included domestic abuse.

Police said they had yet to decide whether he would be remanded in custody.

Hoiby was born in 1997 from a relationship prior to Mette-Marit's 2001 marriage to Crown Prince Haakon, the heir apparent to the Norwegian throne.

He and his step-siblings -- Princess Ingrid Alexandra, 20 and Prince Sverre Magnus, 18 -- were raised together by Mette-Marit and Haakon.

Unlike them, he has no official public role.

After his arrest in September, reported Hoiby was blocked from accessing his mother and stepfather's home.