The Finnish Defence Forces (FDF) have started international cooperation with partner countries for domestic airspace surveillance.
The first such flight, alongside the US Air Force, began on Thursday, according to the FDF.
According to aircraft tracking site Flight Aware, a US Air Force reconnaissance RC-135 Rivet Joint aircraft with the callsign JAKE11 was seen flying along north-to-south patterns parallel to Finland's easter border with Russia on Thursday.
However details about the flights are not being disclosed on grounds of national security.
The FDF said there have been no recent changes in Finland's security situation and that the surveillance flights are part of planned international cooperation.
"Flight operations with international partners is art of normal bilateral and multilateral cooperation. The flights develop the interoperability of the Finnish Defence Forces, improve the common situational awareness and strengthen national defence. The flights show a mutual commitment to developing defence cooperation," the FDF said in a press release issued on Thursday.
The defence forces said that similar flights in Finnish airspace are planned for the future with various types of aircraft, including manned and unmanned aircraft.
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