A Norwegian man in his 20s has been arrested and detained for four weeks on charges of espionage against state secrets.

The man, who worked as a security guard at the US Embassy in Oslo, admitted to sharing information with Russian and Iranian intelligence.

The Oslo District Court's ruling indicates that he collected and shared details about visitors to the embassy.

The suspect, who is of foreign origin, was apprehended at his home without incident.

He has agreed to two weeks of detention, but the Norwegian Police Security Service (PST) sought four weeks, which the court granted.

The investigation is ongoing, with PST collaborating with US authorities and examining large amounts of digital evidence.

The man faces charges under Norwegian law that could lead to a maximum sentence of ten years in prison.