North Korea may be building a new submarine capable of deploying submarine launched ballistic missiles (SLMB) South Korean newspaper "Chosun Ilbo" reported today.

The US Department of Energy’s National Nuclear Security Administration (DOE/NNSA) completed the First Production Unit (FPU) of the W76-2 warhead Feb. 22 at the Pantex Plant in Amarillo, Texas. The W76-2 is a modification of the W76-1 warhead to provide a low-yield, sea-launched ballistic missile warhead capability.