A man watches a television news channel in Seoul showing footage of North Korean submarine-launched ballistic missile (SLBM). Photo: AFP

Just when the world’s focused on North Korea’s land-based missile tests, Pyongyang may be readying a submarine-based missile launch.

38 North, a respected Johns Hopkins University website dedicated to analysis of North Korea, reports that commercial satellite imagery shows unusual activity at a North Korean base used for its submarine-launched ballistic missile (SLBM) program.

Military expert Joseph S Bermudez notes in an exclusive analysis that netting or tarps have recently been strung above a SINPO-class submarine at the base to obscure satellite detection. The last time this happened was in July 2016 when the North tested an SLBM missile.