In what may or may not have been an error, a Russian website recently posted (briefly) a photo and description of “Status-6” a special torpedo with a range of 10,000 kilometers and the ability to avoid any sensors. The torpedo had a nuclear warhead and was described as designed for use against key coastal targets. The large nuclear warhead could destroy a major port city and the radioactivity would delay reconstruction.
From a technical point of view this torpedo made no sense because the fuel required to propel a torpedo 10,000 kilometers (6,000 miles) could not be carried in a torpedo, even one so large it had to be launched from a specially equipped sub or from the missile launch tubes of a SSBN. It was implied that Status 6 used nuclear power, but that would greatly increase cost and complexity and reduce reliability. Russia said the project was classified and the data was taken down soon after it was posted.
This idea is nothing new. Russia looked into developing a similar, but smaller, weapon starting in the 1950s. This one would be launched from a torpedo tube some 30-40 kilometers from the coast at a large target (like a city). Russia never got this proposal into a workable form and it was abandoned.
It is believed Status-6 was another bit of Russian propaganda to support the current Russian government accusation that the United States and NATO is seeking to conquer Russia and part of that involves building anti-ICBM systems that would neutralize Russian ICBMs. Thus the need to describe Status 6 as a weapon that could get past (or well under) current anti-ballistic missile technology. The story is generally not believed by anyone in the U.S. Department of Defense, but those without access to technical experts could be persuaded to believe it.