• A remote textile plant in North Korea’s east may be secretly producing UDMH, the specialized fuel that has enabled country’s long-range missile launches.

The plant is in Hamhung, which Kim Jong-un visited in 2013, above.

The new finding comes from American researchers who used satellite imagery, a technical analysis of the fuel’s production methods, information from a North Korean official who defected, and a set of obscure North Korean technical documents.