At about 5:30 EEST, a Donetsk telegram channel shared a video showing a fire in Russian-occupied Horlivka accompanied by sounds of detonation:
https://twitter.com/EuromaidanPress/status/1561212500426760193
Here is the footage of the same fire in Horlivka filmed from a closer angle:
#Horlivka (Donetsk oblast, occupied) earlier this morning: nice popcorn sounds at another ammo depot pic.twitter.com/PMhSAZKi4k
— English Luhansk (@loogunda) August 21, 2022
Multiple minor detonations of the ammunition imply that it was another Russian military facility that was likely hit by the Ukrainian forces earlier this morning.