They built a military base for this invasion there.
there had been unverifiable reports that appeared to be Russian propaganda of Ukraine staging rocket attacks on it but I suspect it was an accident as this is a hastily constructed base handling heavy ordinance
My first guess is also an accident.
However, there has now been some time for a lot of players to start planning and spinning up some counter-operations. Eventually, the war is likely to come to Russia in some form.
Mark Levin mentioned Dolittle’s Raid to bomb Tokyo, after Pearl Harbor, recommending that the Ukrainians send some operators into Russia. Lot’s of professionals probably had that on their standard checklist of options.
Let’s look to see if it turns out to have been a really constrained Military essential, or just something more prone to industrial accidents.