COPENHAGEN, Denmark (AP) — A Norwegian citizen has been arrested after allegedly meeting with a Russian intelligence officer in an Oslo restaurant, Norway's domestic intelligence agency said Monday.

The man was arrested Saturday after handing over information, the agency said, adding that the alleged actions “could harm fundamental national interests.”

The Norwegian Police Security Service didn’t identify the arrested individual. The man in his 50s met “with what is believed to have been a Russian intelligence officer,” said Line Nyvoll Nygaard, a prosecutor for the intelligence agency.

The security service said the citizen is suspected of violating a Norwegian law that carries a maximum prison term of 15 years.

“We believe that through his work, he had access to information that is of interest to a foreign nation,” Nyvoll Nygaard told reporters.

The suspect's lawyer, Marianne Darre-Naess, told Norwegian news agency NTB that her client denies wrongdoing,

Norwegian media said the case was about industrial espionage.

Norway-based DNV GL, a major global classification society for ships, later confirmed that the suspect was employed for the company. DNV GL is also the largest technical consultancy to the global renewable energy and oil and gas industry.

The man was facing a custody trial before an Oslo court to be held behind closed doors.

Prime Minister Erna Solberg said she had been informed of the case.

Norway’s most recent known spy case involving Russia involved retired Norwegian border inspector Frode Berg, who was sentenced in Russia in 2019 to 14 years in prison for espionage. He was arrested in Moscow in December 2017 and accused of collecting information about Russian nuclear submarines for Norwegian intelligence.

In November 2019, he was part of a three-way spy swap when he and two Lithuanians were freed in exchange for two Russians who had been in prison in Lithuania. While Berg was handed over to Norway’s embassy in Vilnius after he crossed into Lithuania, the spy swap took place at a border checkpoint with the Russian exclave of Kaliningrad.

It was unclear whether the present case was as big as the arrest in 1984 of Arne Treholt, who was convicted of treason and espionage on behalf of the Soviet Union against Norway during the Cold War and given 20-year prison sentence.

Treholt, who was then the Foreign Ministry’s chief press officer, gave the Soviets documents on NATO troop deployments and Norwegian military weaknesses, as well as confidential accounts of talks between Norwegian and world leaders.

He was released from prison in 1992 and moved to Russia.