There is no set formula for the explosive that is used in illegal fireworks. Some of the fireworks that are made in Mexico are so unstable and dangerous that they are shipped wet to prevent them from exploding prematurely. The explosive filler can be set off by friction, heat, impact, sparks or flame. If you have a bag full of illegal fireworks and one of them goes off accidentally, you can assume that all of the fireworks in the bag will go off at the same time. A small amount of fireworks going off at the same time in a vehicle can kill everyone who is in that vehicle and scatter parts of the car in all directions.
Static electricity is everywhere.
It is created by motion. A car driving down the road is creating static electricity as you travel. Wind or walking on a carpet can create static electricity. You can create static electricity by running your fingers through your hair. I am sure that everyone has been shocked by static electricity when they grab a door handle after sliding across a car seat.