North Korea’s oil tanker fleet is especially busy ahead of next month’s anniversary of the founding of the Worker’s Party of Korea, with numerous vessels repurposed to Chinese waters from Russia, the NK News vessel tracker and data from Marine Traffic shows.

Intermittent AIS tracking coverage around the Korean Peninsula often makes it difficult to see up-to-date positional information for the entire oil fleet simultaneously. However nearly every DPRK oil tanker broadcast its position this week, with queues forming at commonly used loading and offloading terminals.

The upcoming celebrations may help account