https://www.bbc.co.uk/news/world-us-canada-56159731 The article doesn't actually specify what it was that he was using or what went wrong.
"A spokesman for state police told the New York Times the device consisted of some kind of pipe, without giving further details."
nothing wrong with making your own fireworks .you just have know what your doing. I started at age 5 now ime 65 . time flies and i still have all my fingers
Such a sad story - a proud dad trying to create a family memory. Moral of the story - Don't play with fireworks or explosives. Let's all be careful out there!