I live relatively near Intel, Folsom California plant. They put on some spectacular drone displays in the night sky without any warning. Sometimes I think there's got to be upwards of 1,000 at a time. Once was a HUGE American flag waving. I think they are testing product before shipping or something. Across the freeway from them, Aerojet used to build and test rocket engines. The noise and smoke plume from those! The sound would rattle windows dozens of miles away and the smoke visible all the way up to Shasta on a clear day.
I'm without doubt our government knows at least where these recent sightings are being launched from and landing. Our tracking systems are way too sophisticated not to. Even when I was in the Air Force, working in Alaska on early warning systems, we had one, called Cobra Dane, that could track as many as 3,000 objects the size of a softball in orbit. I was hired part time by Raytheon to assemble a bunch while stationed there. For tests, we would track a seagull, then focus the phased array on it and smoke it out of the sky, Poof! So if we had that technology back in the 70's, I'm sure we have our ways of vaporizing a simple drone to the point it would not be a bother with the wreckage coming down to earth.