A firework ignited a three-acre grass fire at a park in San Francisco.… CNN 0 173 07.03 09:34 https://www.youtube.com/watch?v=jIRXModg_zQ + 36 https://www.youtube.com/feeds/videos.xml?channel_id=UCupvZG-5ko_eiXAup… + 24 A firework ignited a three-acre grass fire at a park in San Francisco. #fireworksafety