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A cannonball can cause a lot of damage and residents in one Northern California neighbourhood found out the hard way. It happened in the city of Dublin during an experiment by the popular TV show "MythBusters."
Authorities said the show was there to measure the speed of projectiles fired from a cannon.
They started with a cannonball, but it completely missed its target. It was supposed to go through a few water-filled barrels and a concrete wall. Instead, it ended up bouncing off a sidewalk and blasting through the front door of a home.
It then whizzed across a bedroom, where a couple was sleeping.
"They didn't actually hear the ball go through the house. What woke them up was the settling of the sheet rock that woke them up," said Alameda County Sheriff's Sgt. J.D. Nelson.
Nelson, who is also a consultant for the show, said producers have used the cannon that they built at the range more than 50 times without incident.
The ball, travelling at bullet-speed, left a 10-inch hole in the bedroom wall.
But that's not all. The cannonball then ricocheted across the street and smashed through a minivan's window.
The show has been put on hold while investigators look into how this all happened.