At least 28 people were injured Thursday in Simi Valley, Calif., when many of the fireworks at a July 4th celebration ignited too close to the ground. People there caught the accident and posted videos. YouTube.com hide caption itoggle caption YouTube.com The Two-Way VIDEO: California Fireworks Mishap Injures Dozens July 5, 2013 A large number of the explosives went off far too close to the ground. At least 28 people were hurt, though most of the injuries are said to be minor. Onlookers caught the chaos on video.