Smoke and noise was from a firecracker, say cherry bomb or similar, to distract attention away from a hidden shooter in the bushes to escape. With all the people looking and running up toward the knoll, nobody would have noticed shooter crawling out and escaping with muddy knees that was reported. Leaving behind his weapon later removed by city when bushes were trimmed down to remove obvious shooter window seen in the Z-film. When city removed the storm drain at corner of Elm, they also recovered the weapon used to shoot K in the back. Upward angle of bullet could have only come from there.