(CNN) -- Authorities in Norway have launched an investigation into whether the United States conducted illegal surveillance in the Nordic country, the Ministry of Justice told CNN Thursday.
Officials from Norway's Ministry of Foreign Affairs talked to the number two at the American Embassy in Oslo, James Heg, about the allegations on Wednesday, a spokeswoman said.
"Because here at the Foreign Ministry, we have not been informed about this" alleged surveillance, she said, asking that her name not be used.
"We wanted to know.... what these activities included," she said.
"These questions were, however, not fully clarified in this meeting, which is why we now have to seek further clarification of the matter," she said.
"Any violation of Norwegian law is not accepted, regardless of who may be responsible," she told CNN.
The investigation follows a report by Norway's TV2 claiming that the U.S. Embassy in Oslo has been conducting an "illegal systematic surveillance of Norwegian citizens."
The channel claims the embassy has hired former police officers and defense staff to take pictures and register people who behave in a suspicious way in order to stop attacks on American targets in Norway.
U.S. State Department spokesman Philip J. Crowley acknowledged the surveillance program at a press briefing in Washington on Monday, but said Norwegian authorities had been informed.
"The surveillance detection program is something that we've put in place over the last decade. We recognize that our posts around the world are prospective targets and tragically there's a lot of intelligence and actual attacks to back that up," he said.
"All of our activities in Norway are fully consistent with and with the cooperation of the host nation government," he added.
But some key Norwegian authorities deny they had any knowledge of the operation.
Justice Minister Knut Storberget has asked the Norwegian police and the Norwegian Security Police to clarify if they had any knowledge of the U.S. Embassy's alleged surveillance program.
"I wish to bring as many facts as possible to the table. On Norwegian soil, Norwegian law must be followed," Storberget said in a statement.
Martin Bernsen, a spokesman for the Norwegian Police Security Service, told CNN that they knew of "a certain surveillance activity taking place, but not at this scale.
"What we can say is that it is only Norwegian police that should conduct police work on Norwegian territory," he added.
The U.S. Embassy in Oslo responded to the allegations by saying: "Norway is a friend and ally. We are prepared to work intensively to address any questions the Norwegian government might have on this or any other matter."
TV2's report on Wednesday came after a two-year investigation, it said.
The station reported that for the last decade, around 15 to 20 individuals have been working in shifts, 24 hours a day at a secret location in Oslo, located close to the embassy.
The Surveillance Detection Unit (SDU) is said to have been collecting personal information such as vehicle registration numbers and personal information about individuals behaving suspiciously.
These reports were then collected in a database called SIMAS, where information is shared between different U.S. authorities and posts, TV2 reported.
A TV2 reporter asked Crowley about SIMAS at the State Department briefing on Monday.
Crowley did not specifically acknowledge its existence, but said information was shared.
"It is possible when you look at a networked entity like al Qaeda that they might be casing a post in Europe, in the Middle East, in Africa, and so we have a database that shares intelligence and assessment," Crowley said.
Several hundred Norwegian individuals may be in the SIMAS database, according to TV2, which said those people may encounter problems if trying to enter the U.S.