Twenty-eight people sustained mild to moderate injuries after a wooden platform containing live fireworks fell over at Fourth of July show, sending the explosives into the crowd soon after the show began.
Initial reports of ten injuries at the Simi Valley, California fireworks show soon spiraled to 28 by midnight Thursday, reported KTLA, as 20 victims were transported to area hospitals, with eight with less serious injuries given treatment at the scene of the incident.
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Between 8,000 to 10,000 people were attending the show at the Rancho Santa Susana Community Park located near East Los Angeles Avenue when the accident took place, reported the Associated Press.
Most of the injuries were either burns, or similar to the wounds created by shrapnel, and no deaths were reported.
"There was a big boom. Everybody started running down the street. People were screaming,” said Justice Allen, 17, of Simi Valley to the Los Angeles Times of the accident. "Everybody was just terrified. People hid in bushes."
"For some unknown reasons the structure that holds these ordinances collapsed and caused them to be firing into the crowd," said Simi Valley police Cmdr Stephanie Shannon to AP.