Norway has detained a Russian man caught crossing the border in the Scandinavian nation's far north as he returned home with two drones and a cache of photos and videos.
The move comes as Norway is on high alert following several reports of mysterious drone sightings close to offshore oil and gas drilling platforms run by the major energy producer.
Last month's Nord Stream gas pipeline blasts in the Baltic Sea are widely assumed to be the result of sabotage.
The man, named as 50-year-old Vitaly Rustanov, was arrested this week at the border post of Storskog, the only transit point between Norway and Russia.
A judge at a court in Vadso ordered Mr Rustanov to be placed in custody for two weeks in line with a police request.
"There are ... reasons to believe the accused will try to escape judicial proceedings unless he is placed in provisional custody," the judge ruled.
Mr Rustanov was carrying two Russian passports and an Israeli one when arrested attempting to drive back into Russia, he noted.
According to the judge's ruling, Mr Rustanov had admitted flying drones "across the whole country" but denied any wrongdoing.
In Norway since August, he was carrying a partially encrypted four-terabyte stash of photos and videos when arrested.
"He has explained he was in Norway as a tourist visiting somebody," police official Anja Indbjor told the Verdens Gang daily.
"He has explained he photographed and flew a drone for private reasons and indicated he likes taking photos and is a photographer," added Ms Indbjor.
She said that "what we have seen thus far backs up his claim to be a tourist".
Norway, along with several other Western countries, has forbidden Russians and Russian entities from overflying its territory following the February invasion of Ukraine.
Breaking that ban is punishable by a three-year prison term.
Mr Rustanov told police, who indicated he was cooperating with them, he was unaware of the ban.
He had been in Norway since August, visiting a fellow Russian who lives there. Police said the other Russian had also been questioned.
With Russia's invasion of Ukraine having led to a huge fall-off of Moscow's energy deliveries, Norway has overtaken Russia as the main supplier of natural gas to Western Europe.
Following the Nord Stream explosions and drone sightings, Norway increased security around its energy installations.
Norwegian media reported that another drone had been seen late Thursday overflying a gas treatment facility at Karsto in the southwest of the country.
Police urged the public to pass on any information as they sought further clues as to who was responsible.
