Russian TU-95 “Bear” bombers buzzed by Alaska for the second time in two days on Tuesday, flying even closer to the Alaska mainland than during the first flyby, CBS News National Security Correspondent David Martin reports.

The Bear bombers flew about 40 miles off the coast Tuesday. On Monday, they flew about 100 miles off the Alaskan mainland. In response, two U.S. F-22 fighter jets intercepted the Russian planes during Monday’s flight. The second flight was tracked by a radar early warning plane, but apparently no jets were scrambled in response.

There is a classified set of criteria for determining which Russian bomber flights need to be intercepted and which don’t. Tuesday night’s flight did not meet the criteria. Russia is exercising its long-range bomber force. The Russians don’t always include flights down the West coast as part of the exercise, but this time they did.

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No one at the Defense Department regards this as a serious issue, since everyone followed the rules. This was a standard patrol by Russian Long Range Aviation, similar to others historically flown along the West coast. The flight was well into international air space but within the Air Defense Identification Zone (ADIZ). Unlike commercial aircraft, military aircraft are not required to file a flight plan when entering the ADIZ. It’s the U.S. responsibility to see them coming, which they did. Everything went according to the rule book. There was no communication between the pilots – as opposed to the last time.

On July 4, 2015, Russian bombers flew just about 40 miles off the California coast. American jets intercepted the bombers, and Russian pilots wished the Americans a “happy birthday.”