melmothtw,
Just from the beginning of the conflict and thru these days the Ukrainian army is often using BM-21 "Grad" (122 mm multiple rocket launcher) against living quarters. This artillery system
https://en.wikipedia.org/wiki/BM-21_Grad
was developed in SU back in 60's against millions of Chinese who were a real threat in Far East at that time. Quite comparable to a massive bomber attack.
Even more, "Tochka" and "Tochka-U" ballistic missiles (9М79М and 9М79-1, or SS-21 as per NATO classification) were used there in 2014 and 2015. Again, against masses of (their own civil) population in urban areas.