When the Russian Army was approaching Berlin, they kept up a constant barrage of heavy mortar fire, whether or not it was needed. They did this to demoralize and frighten the German population, particularly in Berlin.
The volume of fire was so great that it could easily be heard 100 miles away. It sounded like a distant thunderstorm that never ended.
Fireworks project
https://noqreport.com/2020/06/23/yes-the-fireworks-are-part-of-the-evil-plan-to-destroy-america/