A female photographer was extremely frightened when she heard the words coming from a Siberian, Russian.
"These dull sounds make me really feel aliens are very close," Svetlana Kuzina wrote on personal Facebook.
During the day, it sounds louder and sharper.
At first, she was also afraid to hear "alien-like" sounds in the middle of the night while taking photos of the stars at Ak-Kem Lake .
The " pung poang" sound changes when it is big, at a young age, when it is low, when many people think of whales singing. During the day, it sounds louder and sharper, Kuzina explained.
"After that, I realized that the noise came from the lake and stood there long after taking the photos, feeling very impressed and a little afraid of the lake's singing , " she said. . " After that, I heard this song many times at different times of the day."
According to some experts, the sound is caused by ice sheets.
