There was a huge explosion in Siberia in 1908, called Tunguska explosion or something like that and there are some videos on YouTube. One problem is that the area was so remote, no investigation of the explosion was conducted until 1930.
The explosion is thought to be about 12 megaton, felling big trees in a concentric fashion miles around, being felt in Europe and other countries where earthquakes were recorded.
If it was an asteroid or comet exploding midair, the legends of the locals who witnessed the event do not match. On the other hand, there was a meteor explosion in Chelyabinsk, an industrial city in western Siberia bordering on Europe (this demarcation is artificial) in 2013, about 100 years after the mysterious explosion in Siberia. This event was recorded by multiple dash cams.
Was the Tunguska explosion part of the warfare between underground civilizations? (The defenders caused the explosion before the weaponized meteor reached the ground, so the theory goes)
There is a theory about Tartaria, a lost civilization in Siberia. Some say a timeline shift occurred, and there are traces of lost civilization in unlikely places like Sydney. You can dismiss it as a wacko conspiracy theory, but the fact is, conspiracy theorists always turn out to be right (after a while)