The North American Aerospace Defense Command says it detected four Russian military aircraft flying near Alaska on Monday, less than two weeks after US Army soldiers were deployed to the area as part of a “force protection operation” amid an increase in Russian and Chinese military exercises in the region.

Eight Russian military planes and four navy vessels, including two submarines, have come close to Alaska in the past week.

Japanese fighter jets fired warnings flares against a Russian military aircraft that Tokyo said repeatedly entered the country’s territorial airspace, in an unprecedented move against a foreign plane.

Russia's statement comes after the United States deployed two warships for homeland defense operations to protect Alaska.