U.S. Air Force F-22 stealth fighter jets intercepted two nuclear-capable Russian strategic bombers near Alaska on Saturday, Russia's ministry of defense has confirmed.

The incident, first reported by the Washington Free Beacon, unfolded outside US sovereign airspace as Russia carries out its biggest military drill in modern history.

“Two Alaskan-based NORAD F-22 fighters intercepted and visually identified two Tu-95 'Bear' long-range bomber aircraft flying in the Alaskan Air Defense Identification Zone, south of the Aleutian Islands,” Michael Kucharek, a spokesman for the North American Aerospace Defense Command (NORAD) told the Beacon.

“The two Russian Tu-95 bomber aircraft were intercepted and monitored by the F-22s until the bombers left the ADIZ along the Aleutian Island chain heading west,” Kucharek continued, referring to the air defense and identification zone the U.S. maintains around its borders.

But while the incident resolved peacefully, a defense official told the Beacon that the Russian bombers may have been practicing for a cruise missile strike on U.S. missile defense sites and radars in Alaska.

Alaska, the nearest U.S. state to Russia, contains some of the U.S.'s most advanced radar and missile defense installations, which function as the eyes and ears of much of the U.S. military's strategic assets. If war broke out between the U.S. and Russia, those sites in Alaska represent a likely first target.

Practicing strikes on key U.S. targets roughly fits with the stated goals of Russia's massive military exercise, which is taking place in the country's east. Previous reporting suggested that Russia and China, which is joining parts of the exercise, would simulate nuclear war.

Additionally, the Russian bombers may have been trying to test the U.S.'s response time.

Over the Mediterranean, where Russia and its Syrian ally have been laying siege to Idlib, the country's last rebel stronghold, long-range planes have practiced refueling and extending their reach, Russian media reported.

The Tu-95 is a propeller-driven, Cold War-era bomber that has frequently been intercepted around Alaska in the past. The F-22 is the world's most advanced combat jet and one of the stealthiest planes in existence.

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