BRUSSELS — NATO scrambled fighter jets 10 times on Monday to track and intercept an unusually "rare peak" of Russian bombers and fighters flying over the North Sea, Black Sea, and Baltic Sea, according to a NATO official. "NATO aircraft intercepted six different groups of Russian military aircraft near alliance airspace in less than six hours," the organization said in a statement. The Russian activity across an unusually wide area of European skies came on the same day North American Aerospace Defense Command said it tracked Russian aircraft off the coast of Alaska. None of the Russian aircraft entered the national airspace of NATO nations in Europe and the intercepts were considered safe, but an alliance statement detailed the activity. Norwegian F-16s scrambled after radars detected two groups of Russian military aircraft near Norway"s coastline. The Norwegians intercepted two Tu-95 Bear bombers which flew south over the North Sea. That prompted the United Kingdom to send up Typhoon aircraft and Belgium to deploy F-16 fighters. The Norwegian F-16s later intercepted two Tu-160 bombers over international waters nearby. Separately, NATO radars detected three Russian military aircraft near allied airspace over the Black Sea which was tracked by Turkish, Romanian, and Bulgarian fighters aircraft until they left the area. In another encounter, NATO said Italian fighter jets intercepted a Russian II-38 maritime patrol aircraft which was already being escorted by Russian fighter jets over the Baltic Sea flying from Kaliningrad. CNN reported on Saturday that the US is preparing to carry out a classified war game this summer where a major focus of the scenarios will be how the US should respond to aggressive action and unexpected moves by China and Russia. Tensions with Russia are high, and last week, Secretary of State Antony Blinken called out Russia for "reckless and adversarial actions" at a NATO meeting in Brussels and observed that Moscow has "built up forces, large scale exercises and acts of intimidation, in the Baltic and the Black Sea." "Intercepting multiple groups of Russian aircraft demonstrates NATO forces" readiness and capability to guard Allied skies 24 hours a day, 7 days a week, 365 days a year," Brig. Gen. Andrew Hansen, deputy chief of staff operations at Allied Air Command, said in the NATO statement. NATO aircraft scrambled more than 400 times in 2020 to intercept unknown aircraft according to the alliance. About 90 percent were in response to flights by Russian aircraft. NATO says Russian flights often pose a risk to civilian air traffic over Europe because the Russians often fly without transmitting a transponder code indicating their position and altitude and do not file a flight plan or communicate with air traffic controllers.