NATO has conducted a planned air exercise above northeastern Poland near Russia's Kaliningrad region, according to Polish broadcaster TVP World.
The exercise involved US and Norwegian fighter jets, a NATO E-3A Sentry AWACS surveillance aircraft, aerial-refuelling tankers and a US EA-37B electronic-warfare aircraft.
Estimates of the number of aircraft involved ranged from about 25 to 50.
Poland's Operational Command said Tuesday’s exercise was coordinated by NATO and was unrelated to Russian air force activity.
The operation was intended to strengthen interoperability among allied forces and practice joint air-operation scenarios, according to the command.
The exercise came days after the Bild newspaper in Germany reported details of what it described as a NATO Land Warfighting Concept for responding to a possible Russian attack on the Baltic states.
The reported concept includes potential strikes against missile and air-defence systems in the Kaliningrad region.
NATO has increased military exercises around the strategically important Suwalki Gap, a narrow stretch of territory connecting Poland and Lithuania between Kaliningrad and Belarus.
Allied forces conducted the Amber Shock 26 drills in the area in May.
