Russian nuclear bombers were spotted flying near Alaska this week. The bombers were escorted by fighter jets, floating just outside of U.S. and Canadian airspace. This is the second such sighting since June, sparking the attention of American military jets.

Major Beth Smith, of the U.S. Northern Command and the North American Aerospace Defense Command (NORAD), has said "Over the past week, NORAD has visually identified Russian aircraft operating in and around the U.S. air defense identification zones." There have been about 16 Russian forays in the Alaskan and north Canadian area in the last 10 days.

It is not entirely uncommon to see Russian planes in this airspace, however, the increased number of such planes seems to be triggering some concern amongst the aviation military community, particularly given the increased tension in Ukraine. Smith referred to this number of forays as "a spike in activity."

Smith noted that these were training missions, though a spy plane and anti-submarine plane were spotted among the bombers. However, another defense official told the Washington Free Beacon they believe this is more than just a training flight. The official stated "[Russian strategic nuclear forces appear to be] trying to test our air defense reactions, or our command and control systems. These are not just training missions."

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The Russian military has admitted they have flown in that area. They told ITAR-TASS, "all flights were scheduled in advance and were made in strict compliance with the international rules of using airspace without trespassing the borders of other countries."

This article was originally published at http://www.thewire.com/global/2014/08/russian-nuclear-bombers-keep-roaming-closer-to-us-airspace/375791/

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