Russia is purportedly working on a top-secret unmanned underwater vehicle (UUV), which, once operational, will be armed with megaton-class nuclear warheads Bill Gertz over at The Washington Free Beacon reports. Moscow’s newest arms program, code-named “Kanyon” by the U.S. military, has allegedly been designed to target both naval ports used by the U.S. Navy’s submarine fleet as well as U.S. coastal regions. According to Gertz: Officials familiar with details of the Kanyon program said the weapon is envisioned as an autonomous submarine strike vehicle armed with a nuclear warhead ranging in size to “tens” of megatons in yield. A blast created by a nuclear weapon that size would create massive damage over wide areas. A megaton is the equivalent of 1 million tons of TNT. Additional details on the program are murky. “This is an unmanned sub that will have a high-speed and long-distance capability,” one source states without offering further information.