In 1982 Russian sailors taking diving training in Baikal Lake, Siberia took a dive of 164 feet, and 3 humanoid creatures about 9 feet in height floated up toward them.
The creatures had silver silhouettes and transparent spheres on their heads shaped like open umbrellas.
The creatures and the Russian divers stared at each other until the creatures descended back into the depths.
The sailors surfaced and told their commander what had happened and were instructed to catch one of the humanoids so it could be examined.
Seven divers dived back into the lake with snares and wires to catch one of the humanoids with.
The humanoids rose from the murky depths when they saw the divers, and one of the divers tried to catch one.
The attempt failed, and the humanoids unleashed high powered sonar waves that tossed the Russian divers back up to the surface.
The divers, having surfaced too fast, developed decompression sickness, and three of them died from it.
As to whether the humanoids were aliens, no one knows, but if this account is true, I suspect they were.
Bob Boyd