Russia is building upon military bases, hardware and underground storage facilities on its Arctic coastline, with bombers, MiG31BM jets and new radar systems close to the Alaskan coast, according to satellite images provided to CNN by space technology company Maxar.
Included in the buildup is the Poseidon 2M39 unmanned stealth torpedo, a so-called super-weapon powered by a nuclear reactor. Russia quickly developing the armament and tested it in February, with further tests planned this year.
To counter the buildup, NATO and the U.S. have also moved equipment into the area in the past year, including the U.S. military's stealth Seawolf submarine as well as its B-1 Lancer bombers, which recently flew over the eastern Barents Sea.
While the increase of Russian military assets has taken place inside Russian territory, U.S. officials are worried Moscow may move use its forces to take over areas of the Arctic outside its borders.
The buildup has been all the more apparent in recent days, with Russia holding military flights near Alaskan airspace and submarine activity in the Arctic.
In late March, three Russian nuclear ballistic missile submarines simultaneously broke through several feet of ice in the Arctic in a military drill. And last week, Russia flew jets and bombers near Alaskan airspace, including 10 times on Monday alone.