A dormant North Korean port near the border with Russia has sprung back to life, fueling what experts say is a burgeoning trade in arms destined for the frontlines in Ukraine that is simultaneously bolstering the anemic economy managed by Kim Jong Un.

Satellite imagery of the Najin port taken from October to December shows a steady stream of ships at the facility, hundreds of shipping containers being loaded and unloaded, and rail cars ready to transport goods.