The Russian navy has declassified records of Cold War UFO sightings in 2009 and it turned out that over 65 percent of UFO encounters are connected with waters, oceans or lakes.
Incidents have been cited, were six unidentified objects that followed a nuclear submarine in the Pacific. "UFOs have been sighted in the deep parts of the Atlantic, the southern part of the Bermuda Triangle and the Caribbean," a Marine was quoted as saying. Below the surface objects have been reported that rose from the water and flew away.
There is also a captivating account of a group of military divers in Lake Baikal, Russia in 1982 the deepest lake in the world, who encountered a group of humanoid beings in silver suits at a depth of 160 feet.

One of the most chilling encounter revealed in Russia's declassified UFO reports doesn't involve unidentified submersible objects (USOs) or any other type of craft, but an alien encounter. 👽
Lake Baikal is located in the mountainous Russian region of Siberia in an active continental rift zone and has a depth of 5.387 ft (1.642 m).
In 1982, Russian Navy divers were conducting a research mission underneath the ice-layer of Lake Baikal, when the group of seven suddenly noticed being observed by a handful of humanoid creatures. They appeared to be about 9 ft (2,74 m) tall, wearing translucent helmets and "very tight-fitting silvery suits".

Underwater Alien Description:
Humanoid Creatures
Height: 9 feet / 2,74 metres
Translucent "Dome-like" Helmets
Tight Silvery Suits
No further equipment like oxygen tanks or masks has been observed.
The divers made an attempt to capture one of the creatures, but according to the Russian report, the humanoid creatures reacted with a sudden blast that immediately propelled the divers to the surface of the lake.
Since the group of divers has encountered the underwater aliens at around 160 ft (50 m) depth, three out of the seven Russian Navy divers have lost their life due to decompression issues from rising to the top too quickly.
Attention 🚨 This story has been reported by a handful of legitimate UFO sources, but unfortunately I have not been able to find the official Russian navy reports that allegedly have been declassified and reported this story!
If you have more information about this Alien encounter or can link the source files of the declassified UFO Russian-Navy reports, please drop me a message below 👇🏻