injuries in what should have been a joyous fourth of july. let's go to los angeles. something went wrong in simi valley. about two minutes into the show -- >> that wasn't supposed to happen. >> you can hear it. that wasn't supposed to happen. that was an explosion. fireworks going into the crowd. spectators scrambling to get out of the way. >> a round, cylinder block hit the person next to me, not hard, but did impact her. >> at least 28 people were injured. most of the injuries were burns or shrapnel wounds.