North Korea recently conducted a third test of a new submarine-launched ballistic missile (SLBM) that is part of Pyongyang’s expanding nuclear arsenal, according to US defense officials cited by the Washington Free Beacon. The test took place on April 22 from an underwater test platform near the coastal city of Sinpo in the southeast of the country, and tested what the US is calling a KN-11 missile. The test appears to have been successful, and is the third KN-11 test showing the high-priority of the nuclear missile program for North Korea. Previous tests in January and last October were from a sea-based platform not underwater and a land-based platform.