U.S. fighter jets Monday intercepted a half-dozen Russian warplanes off the coast of Alaska and kept tabs on the aircraft until they left the region, authorities said Tuesday.

The F-22 fighters intercepted four Russian bombers and two Russian fighter planes entering an area designated as the Alaskan Air Defense Identification Zone.

The Russian nuclear capable long-range bombers flew into the Air Defense Identification Zone, which extends approximately 120 km off Alaska’s western coast.

The Russian bomber flights are seen by U.S. military officials as part of Moscow’s effort to train its military for a potential crisis while simultaneously sending a message of strength to adversaries.

This latest intercept comes amid tensions with Russia on a wide range of geopolitical issues and a week after Secretary of State Mike Pompeo met Russian President Vladimir Putin in the resort town of Sochi where he warned Russia about interfering in U.S. elections, taking a tougher public line than U.S. President Donald Trump on the issue.

U.S. F-22 fighter jets and an E-3 Airborne Early Warning and Control System from North American Aerospace Defense Command “positively identified and intercepted a total of four Tupolev Tu-95 bombers and two Su-35 fighters entering the Alaskan Air Defense Identification Zone (ADIZ) on May 20,” NORAD said in a statement.

“Two of the Russian bombers were intercepted by two F-22s, and a second group of bombers with Su-35 fighters was intercepted later by two additional F-22s, while the E-3 provided overall surveillance,” NORAD said, adding that “the Russian bombers and fighters remained in international airspace and at no time did the aircraft enter United States or Canadian sovereign airspace.”

The Russian Ministry of Defense confirmed the incident in a tweet Tuesday, saying the Tu-95 bombers “made scheduled sorties over the neutral waters of the Chukotka, Bering and Okhotsk seas, as well as along the western coast of Alaska and the northern coast of the Aleutian Islands.”

“At certain stages of the route, Russian aircraft were escorted by #F22 fighter jets of the #USAF. The total flight time exceeded 12 hours,” the ministry added.

U.S. officials say Russian bombers and jets have flown in the area several times a year for the last few years and have similarly been intercepted by U.S. or Canadian jets operating as part of NORAD.  (SD-Agencies)