Crown Princess Mette-Marit of Norway is pictured for the first time since her son was charged with assault

Crown Princess Mette-Marit has been pictured for the first time since her son was arrested after a serious incident on August 4.

Marius Borg Høiby, 27, the stepson of the heir to the Norwegian throne, Crown Prince Haakon, is under suspicion for causing bodily harm and criminal damage, Oslo police said Wednesday.

But Mette-Marit and her husband Haakon refused to let the royal shock deter them from their plans this weekend - with the royal couple photographed enjoying the Olympics on Saturday.

The royal mother was full of smiles as she cheered on athletes in the Men's 5000m final at the Stade de France in Paris, on Saturday, after watching the gold medal handball match between Norway and France. 

Mette-Marit - who also joined her husband on Friday to watch the athletics - put on an enthusiastic display, waving to crowds whilst by the Prince's side, despite the news of her son's arrest.

Crown Princess Mette-Marit has been pictured for the first time since her son was arrested after a serious incident on August 4

Marius Borg Høiby (pictured with Prince Haakon of Norway), 27, the stepson of the heir to the Norwegian throne, Crown Prince Haakon, is under suspicion for causing bodily harm and criminal damage, Oslo police said Wednesday

The royal couple also posed together in sweet photographs shared to the Norwegian Royal Family's Instagram page this weekend as they celebrated the Olympics.

Marius Borg Høiby, the son of Mette-Marit from a previous relationship, was arrested last weekend on suspicion of assaulting a woman, police said on Wednesday.

Police said they were called to an Oslo address early Sunday after an overnight altercation in an apartment.

A man in his 20s was arrested over the incident and released from custody the following day, police said in a statement.

'As it has been made known in several media that this (person) is Marius Borg Høiby, the police confirm that it is Høiby who is a suspect in the case.'

Police said he was suspected of causing 'bodily harm and damage'. They did not identify the woman, saying only there was 'relationship between the accused and the victim'.

Høiby faces preliminary charges of bodily harm and criminal damage, one stage short of formal charges.

Police said they had 'no information that the victim suffered serious injuries'. The apartment where the incident took place appeared to have been destroyed, according to Norwegian tabloid Dagbladet.

Mette-Marit and her husband Haakon refused to let the royal shock deter them from their plans this weekend - with the royal couple photographed enjoying the Olympics on Saturday

Mette-Marit - who also joined her husband on Friday to watch the athletics - put on an enthusiastic display, waving to crowds whilst by the Prince's side, despite the news of her son's arrest

While Høiby was raised by Mette-Marit and Haakon together with his step-siblings, 20-year-old Princess Ingrid Alexandra and 18-year-old Prince Sverre Magnus, unlike them he has no official public role.

The case was top news in Norway where the royals are popular.

Norwegian news agency NTB said that Mette-Marit had postponed a planned trip to attend the Olympic Games in Paris while her husband Haakon traveled to the French capital. The reason for the postponement was not given.

The Norwegian Palace confirmed to local media that the Crown Princess has decided to 'temporarily postpone' her trip.

'The Crown Princess has temporarily postponed her departure and hopes to travel down later', the Palace's communications chief wrote in a text message to Se og Hør.

In Paris, Haakon told Norwegian reporters that 'it is a serious matter when the police are involved in the way they are, but at the same time it is not right for me to go into the details of the case.'

Øyvind Bratlien, who has expertise in high-profile criminal cases, has been hired by Marius Borg Høiby as his defence lawyer. 

In a statement to Se og Hør, Bratlien said: 'The charge concerns assault, which under the law is the least severe form of violence. 

Crown Princess Mette-Marit and Crown Prince Haakon watch the athletics at the Stade de France

The royal mother was full of smiles as she cheered on athletes in the Men's 5000m final at the Stade de France in Paris, on Saturday, after watching the gold medal handball match between Norway and France

'Neither my client nor I have been informed of the full details of the case, and he has not yet given a statement, on my advice.'

The police's security service (PST), which is responsible for the security of the royal family, confirmed to Nettavisen that they are aware of the incident. 

'We can confirm that PST was informed shortly after the incident. But we do not want to comment on the case further and we refer the Oslo police district for statements', said Martin Bernsen, senior adviser in PST, to the newspaper. 

According to Lovdata, the Norwegian foundation which publishes judicial information, bodily harm can be punished 'with a fine or imprisonment of up to one year, anyone who commits violence against another person or physically violates him in any other way is punished'.

If the charge is extended to grievous bodily harm the penalty can be up to six years in prison.

Growing up, Høiby made public appearances with his mother, stepfather and half sister Ingrid Alexandra (who is the future queen of Norway) and half brother Prince Sverre Magnus on occasions such as national day.

Norway's Royal Household has been rocked by the news that Crown Princess Mette-Marit 's son was arrested after a serious incident on August 4 (pictured with Princess Ingrid Alexandra, Crown Prince Haakon and the Crown Princess in 2022)

When he turned 20 the royal court announced he was stepping away from public life and his profile was removed from the family's official website

However, when he turned 20 the royal court announced he was stepping away from public life and his profile was removed from the family's official website.

'Høiby will not conduct any official activities on the Royal Family's behalf,' a statement said, 'on the basis of his wish to live outside the public eye.'

His mother Crown Princess Mette-Marit also published an open letter on the court website, saying: 'Marius is, and will continue to be, a vital member of our family. He has always had a public role that has been very difficult to define.'

'Unlike his siblings, he has no official duties. He won't have a public role and is not a public person. Marius became a symbol for the unusual choice we made when we married.'

Marius was previously linked to heiress Linn Helena Nilsen, but the couple split in July 2017.

Femail has contacted Norwegian Royal Palace for comment.