A major construction project at a North Korean long-range nuclear missile factory has slowed in recent months in a possible sign of resource or project direction issues, NK Pro analysis of satellite imagery has found, after work started with urgency last summer.

Planet Labs imagery shows that basic framework construction on two large buildings covering around 2.5 acres (1 hectare) outside tunnel entrances at the Thaesong Machine Factory near Pyongyang stalled with little progress between early December and mid-February.

While it remains possible that renovations or installation of new machinery has continued inside the mountainside tunnels, the