Thanks for the link. There sure was a large amount of smoke from the event.
Low level white smoke indicates a hobby level. From the smoke in the pictures it looks like a hobby rocket was fired. Very amateurish.
Every army/navy store has hundreds of that modern shell container. Hard to trace. You don't have to give a name or anything to buy one of those tin cans.
This guy/gal is a sure amateur with a decent AM plan.