Can confirm: one of the public schools in Mariupol got hit exactly this way and lots of Ukies bought it. (dead soldiers, yellow armbands.) They were using the gym as a barracks, and classrooms for whatever else.
The Russians also torched one of the schools in Kharkov that was also being used by the defenders there. That school burned to the ground.
How did you confirm?
I scan twitter for cell phone vids in the all the conflict cities twice a day, following the advance of the war.
Try looking at Intel Slava in Telegram
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