OSLO (Reuters) - Russia was the likely culprit behind the disruption of GPS navigation signals over northern Scandinavia during recent NATO military exercises, Norway’s defense minister said on Tuesday.

Finnish Prime Minister Juha Sipila speaks during the inauguration ceremony for Nokia's building of knowledge in Alfragide, near Lisbon, Portugal October 2, 2018. REUTERS/Rafael Marchante

Finland’s air navigation services a week ago issued a warning to air traffic due to large-scale GPS interruption in the north of the country.

Norway posted a similar warning at the end of October, days before the start of Trident Juncture, NATO’s largest military exercise since the Cold War involving 50,000 troops in an area stretching from the Baltic Sea to Iceland.

Finnish Prime Minister Juha Sipila said on Sunday it was “possible that Russia has been the disrupting party in this. Russia is known to possess such capabilities.”

The Kremlin dismissed Finland’s allegations on Monday as groundless.

“We have the same problem (as Finland). We think it can also be part of a Russian exercise,” Norwegian Defence Minister Frank Bakke-Jensen said in an interview with Reuters on Tuesday.

“The first time it happened was during Zapad,” he said, referring to a 2017 military exercise conducted by Russia and Belarus. “Also on later occasions ... including during Trident Juncture,” he said.

Norway’s defense ministry later told Reuters that jamming took place between Oct. 16 and Nov. 7, and was registered as coming from “Russian land forces on the Kola Peninsula,” a Russian region neighboring Arctic Norway dotted with naval bases and restricted military zones.

Trident Juncture ran for two weeks from Oct. 25. A command post exercise, involving commanders and their staffs at headquarters, will start on Thursday and last until Nov. 23.

Bakken-Jensen was speaking on the margins of a meeting of Nordic defense ministers in Oslo. Nordic countries are tightening military cooperation at a time when security challenges are becoming more complex and demanding, according to a signed pledge.

Norway, Denmark and Iceland are NATO members. Sweden and Finland are not, but have been cooperating more closely with NATO and their troops are taking part in Trident Juncture.

Finnish Defence Minister Jussi Niinisto told Reuters on Tuesday he was concerned about the danger the GPS jamming posed to civilian traffic. “It worries us that civilian airplanes suffered from this problem,” he said, adding that he had raised the GPS issue at Tuesday’s meeting.

Norway had done the same, Bakke-Jensen said, adding that Oslo was worried because GPS is used by civilians such as fishermen, shippers and ambulance planes.

Denmark’s Defence Minister Claus Hjord Frederiksen said Russian denials of their involvement were not convincing and said the GPS jamming incident was another sign of Russia’s “aggressive” behavior towards neighboring countries.

“If falls in line with the intimidation that they use all the time in the Baltic States, but also when we have ships in the Baltic Sea, and they sometimes simulate attacks against the ships,” Frederiksen said.