This story has been updated with additional information from U.S. Central Command about the sinking of an IRGCN corvette. An American attack submarine sank an Iranian Navy ship off the coast of Sri Lanka,

The ocean can look calm and inviting from the shore, but a new deep water clip has reminded people just how unsettling the world below can be. Filmed from inside a submarine, the footage shows a shadowy, oversized creature drifting past a viewing window ...

After a U.S. submarine sank Iran’s IRIS Dena with a Mk 48 torpedo, attention turned to the Navy’s primary undersea weapon that first entered operational service in 1972.