>> fortunately, the train explodes just outside of town and no one is injured by the blast. >> another mile down the road, it had been right here in the middle of our town. it could have been a really messy deal. >> after the explosion, the fire eventually burns itself out. >> all 26 years of flying and all the news that i've covered, it will be one of the things that will stick in my mind just from the fact it was such a large ball of fire and it came so high. >> oh, it just blew up. my god! my god! >> whether the cause is mechanical failure or human error, when combustible materials get out of control, you can expect big fires, big explosions and big booms. i'm contessa brewer. that's all for this edition of "caught on camera."