Recently I was onboard a commercial airliner and we had just landed and were headed for the gate. I cannot remember exactly which airport but it was either Schiphol(Amsterdam Airport) or Bristol. As we were taxiing I was looking out of the window and saw an object(?) fall vertically into my eyeline from about 10 m up. This object was maybe 50 m away and was at the edge of an intersecting adjacent runway/road and the grass. I noticed it because it had a faint trail of smoke emanating from it. At around 3 m above the ground it ignited, there was a short white flash and it made a small white cloud of smoke that lingered for a short while.
Does anyone know what this might have been? It was almost like a flare/firework (which makes no sense at an airport) so is there another explanation?