"We haven't seen this sort of level of activity for a couple of years," John Cornelio, a spokesman for the U.S.-Canadian North American Aerospace Defense Command (NORAD) told CNN after the last of the April interceptions. He made sure to add that the flights were not “unprecedented" or "unusual."

CNN later said American officials downplayed the intercept as routine and uneventful. This is hardly the first time the Raptors have intercepted Russian aircraft near America’s coastlines. In April 2017, F-22s, along with Canadian CF-188 Hornet fighters, conduct four similar intercepts in as many days. E-3 Sentry AWACS planes have helped direct some of these operations from the air.

On the night of May 3rd, 2017, two Su-35S fighters, without an visible missiles, escorted a pair of Tu-95MS Bear bombers to within 50 miles of Alaska. An A-50 Mainstay radar plane was also in the area at the time, but remained well clear of U.S. territory. Two F-22s quickly flew to meet the incoming Russian planes. Unnamed sources told Fox News , which first reported the incident, that the Raptors were already airborne on patrol near Chariot, Alaska when they were ordered to intercept. The Russian flight may have been spurred by America's massive and highly sensitive Northern Edge exercise that is currently underway in the region.

Underscoring ongoing tensions between the two countries, American F-22 Raptor stealth fighters have intercepted Russian Su-35S Flanker-E fighter jets as they escorted heavy bombers on mission near American air space. For reportedly the first time ever, Russia has added these advanced fighter jets to long-range bomber patrols near Alaska.

There has been a notable increase in these flights since 2014, when Russia forcibly annexed Ukraine’s Crimea region. In response to this aggression and the Kremlin’s subsequent revanchist moves elsewhere in Ukraine and in Syria, the United States and its NATO allies stepped up surveillance operations and training exercises along Russia’s western borders. At the same time, Moscow accelerated bomber patrols along America’s borders. In addition, in 2014 and 2015, the Kremlin had even sent out bombers towards Alaska with older members of the Flanker family as escorts. However, the May 2017 flight was the first time in over a year any Russian fighters had accompanied bombers on one of these excursions.

AP An Su-35S.

Regardless of the relative frequency of these operations, the May 2017 meeting is still significant, because it was the first time the Kremlin has decided to send its newest Su-35s out of one of these missions. Plane maker Sukhoi delivered the first of these production Flanker-Es to the Russian Air Force in 2012. Compared to older Su-27 and Su-30 aircraft, the Su-35s have small refinements in their overall shape, new engines, and updated avionics and sensors. Though still a fourth generation design, Russia says Flanker-Es can supercruise (fly faster than the speed of sound without the use of afterburner) for extended periods and potentially launch missiles while doing so. This tactic would impart additional speed on a weapon at launch, making it harder for opponents to evade them. On the other end, improved, independent 3D thrust vectoring could make the jets even more maneuverable adversaries. On top of that, the aircraft has a quick-scanning Irbis-E passive electronically-scanned array (PESA) radar and an electro-optical system that includes a laser range finder and long-range infrared search and tracking capabilities that stealthy fighters cannot hide from. On top of that, the jets reportedly have a powerful electronic warfare suite to jam and confuse hostile radars. Taken together, the Russians have boasted, without much in the way of public evidence, that this combination could allow the jets to better detect low-observable jets such as the F-22 and F-35.

Lockheed Martin F-22s flying a major high-volume missile shoot test series out of Edwards AFB.