The Northern Response military exercise is taking place in northern Finland, Sweden and Norway.
It happened in Birkvik in Narvik on Saturday.
Police told NRK that the four were foreign nationals, but did not mention the nationality of those arrested.
The Police Security Service (PST), corresponding to the Swedish Security Service, is also notified.
“We take all illegal drone flights very seriously,” he says. Johnny CarlsenNorwegian defense spokesman for NRK.
The exercise is not performed in Birkvik, but restrictions apply there as well.
Swedish action after drone warning
Defense Forces Communications Mary Teasater I still don't want to comment on information about fighter planes in Skåne.
“The armed forces conduct operations at all hours of the day, all year round and throughout Sweden. I cannot comment or go into detail about this type of work,” she told Aftonbladet.
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