North Korea is continuing to develop submarine-launch ballistic missile systems, satellite imagery published Thursday suggested.
According to a report from 38 North, a program of the U.S.-Korea Institute at SAIS providing analysis of events in and around North Korea, the country is continuing work on the development of both the KN-11 submarine-launched ballistic missile, also known as the Bukkeukseong-1, and the GORAE-class experimental ballistic missile submarine.
The report, citing commercial satellite imagery from the Sinpo South Shipyard, indicated that North Korea had finished work on the GORAE-class submarine.
"Unidentified work on the GORAE-class submarine during the past two months appears to have been completed. A heavy crane, engaged in that activity, has been moved to the pop-up test stand for work on the support tower," the report read.
"Construction and refurbishment continues at halls that will be capable of building submarines larger than the GORAE-class when completed."
The positioning of the tower and the test stand at the Sinpo South Shipyard captured by satellite imagery indicated that North Korea is prepared to move swiftly to conduct a pop-up test of a submarine missile when ready.
"The removable tower—moved to the test stand to support a rocket engine, missile or launch tube and then removed—has remained in place for the past two months, allowing the North to more quickly conduct a pop-up test," the report explained.
However, the developments revealed by the latest analysis of satellite imagery represent an "emerging threat" and not a "current threat," 38 North cautioned.
"Deployment of such operational systems will be an expensive, time-consuming endeavor for North Korea and there is no guarantee of success. Regardless, these programs require continual monitoring to ensure appropriate responses are in place if or when they reach fruition," the report read.
North Korea has conducted a number of submarine-launched ballistic missile tests since November 2014, some of them less successful than others. In December, the country successfully tested a KN-11 submarine-launched missile following a botched test in November.