They were essentially homemade bombs disguised as tennis balls. Here's what you need to be aware of in case you stumble upon something similar.

The incident happened in Northern Utah, but its something I've never been aware of and it makes me nervous that this could become a dangerous trend across the country.

Inside the tennis balls were hundred of match heads and a striking device. The tennis balls had then been wrapped in electrical tape and one exploded when it rolled off the porch of a child's home in Clinton, Utah.

According to KTVB, the explosive tennis balls were just left in someone's front yard. Police say the incident could have been deadly had the tennis balls exploded in someone's hand. Luckily, they did not.

Similar devices have not been found in the area, but if you see a tennis ball wrapped in electrical tape don't pick it up and call the authorities.