a box of rockets ignites at a fireworks factory in denmark. explosions spread across 2,000 tons of fireworks. >> explosions on top of explosions. so before one's finished, there's another one exploding. >> i mean, it's beautiful to look at, but it's also terrifying, because you just realize this is like a lot of gun powder. >> a massive explosion shoots a fireball hundreds of feet into the air. >> i mean, there's a guy holding a camera trying to capture it. and he has to, like, hide behind a car. it's just rocking the land beneath him. >> the shockwave is so powerful, it registers as a magnitude 2.0 earthquake. >> the poor people of this town were terrified. >> finally the fireworks show that nobody wanted comes to an end. the disaster kills one firefighter and destroys more