We have smaller versions of those in Mexico. They are fairly terrifying when coupled with the general disregard for safety around fireworks there.
Most terrifying though is that there is a festival that reenacts the christians battling the romans or something like that, but in our town has morphed into the christians fighting the government. The people playing the christians line up in front of the main church and the romans line up across the central plaza, which in our square is a large government building. Then the christians and the government battle start shooting fireworks across the square at one another for an hour or more. This takes place at like three or four in the morning. It's insane.
Skip to 1:40 in this video for a taste of the action that cannot possibly do it justice... This video is shot from the bell tower of the main church, so gives the christian perspective.