Two F-16 jets from a NATO base near Bodo, well above the Arctic Circle, followed the Russian planes, Aftenposten reported. The Norwegian jets returned to base within 45 minutes.

The Blackjacks headed toward Britain, where they were met by RAF jets.

Russia claims its jets are involved in training flights, although observers believe President Vladimir Putin is making a display of Russian military power. The Norwegian goal, when Russian planes are detected, is not to stop them but to identify them, track their movements and demonstrate nothing can enter Norwegian airspace without detection.

Later in the day, a man in a car dropped off a suspicious package weighing more than 30 pounds outside the Norwegian Northern Military Command headquarters in Bodo. The package was taken to a soccer ground for dismantling.