Cities and town all over America lit up the skies with their Fourth of July fireworks shows yesterday, but not all of them were so delightful. In the worst pyrotechnic accident, 28 people were injured in Simi Valley, California, after several inadvertent explosions sent fireworks shooting off into watching crowds and nearby neighborhoods. In this video (via LAist.com), you can see the moment when the fireworks begin exploding on the ground and blasting off in the wrong direction.

Another video shot at ground level gives a better sense of the chaotic scene. Organizers say a platform set up to hold the fireworks tipped over or collapsed, causing the fireworks to be launched in the wrong direction. Many of the spectators were less than 1,000 feet away.

The incident was reminiscent of last year's debacle in San Diego, when the entire stock of fireworks set up for the annual "Big Bay Boom" went off all at once in a single spectacular fireball. In case you were wondering, this year's event went off without a hitch.  

However, there were other 4th mishaps last night. In Windsor, Colorado, sparks from a fireworks show started a large grass fire in the park where the public had gathered for the festivities. Luckily, fire crews were on the scene and able to contain it quickly. And in Seattle, someone setting off illegal fireworks inadvertently set a boat storage facility on fire, causing more than $1 million in damage.

There were other non-firework related tragedies on the Fourth, as well. A seven-year-old boy in Oklahoma was killed yesterday when he fell off a float during a parade and was accidentally run over. In Maine, a man died after the tractor he was driving in a parade was hit by a fire truck and rolled over on top of him. Earlier in the day, that same parade had to be re-routed because of a man firing his gun into the street from his second-floor apartment. No one was hurt in that incident.

Obviously, the vast majority of Fourth of July celebrations took place without incident and a good time was had by almost all. But still there's still two more days left in this weekend — or three, depending on where you work — so it never hurts to be reminded that fire is still fire and people who don't play it safe on this holiday can get seriously hurt. Have fun ... but watch yourselves out there.