Flying object over Kopitoto, Bulgaria

This observation was made on 07 August 2016, between 21:05 and 21:10, over "Kopitoto" tower, near Knyazhevo district in Sofia, Bulgaria. Probably is more correct to say over Vitosha mountain.

At first it was a bit further and smaller and looked a bit like plane's lights, but pretty fast it was clear that it moves somewhat irregularly and the light is too big for a plane. Then it looked like plane of fire, accident maybe. Then it got a bit bigger or closer and didn't look like anything, but the speed was probably 100-200 km/h and the distance 1-2 km, but I may be wrong, there was no way to judge it correctly.  Then the light got extinguished and it proved to be dark object somewhat triangularly shaped and spinning, while getting closer and closer and dropping down. Also there was no sound, the speech you can hear is Bulgarian.

I filmed it with Samsung S4, the camera is not very good and it looked much clearer and bigger on live.

I'd like to see a real UFO or extraterrestrials, but here I am 99% convicted its something human-made, maybe some kind of toy or else. I'll appreciate deeply any ideas about what I've just seen.