It sounds like the classic science movie "The Abyss" — only in Russian.
The Russian Navy has declassified its records of UFO encounters, many of which take place in or around water, reports the Web site of the English-language Russian news channel Russia Today.
"They are most often seen in the deepest part of the Atlantic Ocean, in the southern part of the Bermuda Triangle, and also in the Caribbean Sea," said one naval intelligence officer quoted by the Web site.
Another incident cited involved six unknown objects that followed a nuclear submarine in the Pacific. When the sub surfaced, so did the objects — which then lifted themselves out of the water and flew away.
In perhaps the most compelling account, military divers in Siberia's Lake Baikal, the world's deepest lake, encountered "a group of humanoid creatures dressed in silvery suits" at a depth of 160 feet. Three humans died during the ensuing chase.