Norwegian authorities have detained a Russian man and charged him with flying a drone, as Europe's largest gas supplier seeks  to tighten its security against Russia.

Norway police said the 51-year-old man was arrested on Friday at the airport of the arctic town of Tromso while carrying a drone and camera equipment. 

It is the second such arrest this week. On Friday, a Norweigan court ordered the two-week detention of a 50-year-old Russian national, after he admitted to flying two drones over the country, potentially over critical energy infrastructure.

In recent weeks, there have been numerous drone sightings near Norway's offshore oil and gas platforms.

The Scandinavian country banned Russian companies and citizens from flying over Norwegian territory after Russia invaded Ukraine in February. Violating that ban is punishable by a three-year prison term.

Norway more recently also ratcheted up security following explosions that targeted the vital Nord Stream gas pipeline in the Baltic Sea last month. 

What do we know about the latest drone incident?

Police said the Russian national admitted to flying a drone in Norway. He said he entered the country on Thursday via the northern border point of Storskog — the only border crossing between Norway, a NATO member, and Russia. He said he was headed to the Arctic Svalbard archipelago.

The border between Russia and Norway is 198 kilometers (123 miles) from Arctic land.

Security forces said they confiscated photographs he had taken of an airport in the northern town of Kirkenes, as well as photos of the Norwegian military's Bell helicopters. Police also confiscated photography equipment including a drone and a cache of memory cards.

Police are seeking a court order to detain the suspect for four weeks, the Reuters news agency reported.

The case also involved the Norwegian Police Security Service (PST).

Why has Norway tightened border security?

As European states seek to reduce reliance on Russian energy, they have turned to Norway to help supply natural gas. 

Last month, explosions ripped up two gas pipelines running through the Baltic Sea that had been built to bring Russian gas to Germany. Those blasts occurred in the exclusive economic zones of Denmark and Sweden, just beyond the reach of their territorial waters, and were widely thought to be the result of sabotage.

While Russia has not been directly blamed for the blasts, Western countries have implied they believe Moscow could be behind the incident. Moscow has been excluded from partaking in the official investigations into the explosions carried out by the Danes and the Swedes.

rmt/nm (AFP, Reuters)