Police officials investigate a site in Simi Valley, Calif., Friday July 5, 2013 where an explosion Thursday injured more than two dozen people at a fireworks display. The explosion occurred when a wood platform holding live fireworks tipped over, sending the pyrotechnics into the crowd of spectators.
SIMI VALLEY, Calif. — When a July Fourth fireworks display exploded and sent red and white bursts into spectators at a Southern California park, Paulina Mulkern saw shrapnel headed straight for her 4-year-old cousin.
Mulkern pushed the girl under a lawn chair, and then shielded her 7-year-old cousin with her body as scorching debris flew overhead.
"You feel the big old heat come right over your back," she said Friday, still shaking as she recounted the explosion the night before that left her hospitalized with bruises and red marks on her back.
Thirty-nine people were injured as many in the crowd of thousands fled for safety. The victims, from 17 months to 78 years old, had burns and shrapnel wounds, and some were trampled, authorities and hospital officials said. The injured included 12 children.
Only three remained hospitalized Friday night.
Mulkern said she went into shock after being hit by a flying piece of debris, trembling badly as she was carried to a road where rescuers stripped off most of her clothes and wrapped her in a blanket.
"I was really terrified. Every time someone launched a firework it got me into panic mode and they just told me, ignore the sounds around you and concentrate on your breathing," she recalled.
Police in Simi Valley, northwest of Los Angeles, said it appeared a firework exploded prematurely in its mortar, knocking over others and aiming them across the field. Fire investigators, however, said later they had not yet determined a cause.
Police based their initial statement on the accounts of witnesses, who said a rack of fireworks fell over, said Ventura County Fire Capt. Mike Lindberry.
Among other key questions investigators were trying to answer was whether the pyrotechnics display was set far enough away from spectators, and even if all the rules were followed, whether those guidelines needed to be revised so that the public is kept farther back from launch sites.
Regulations require crowds be kept 70 feet away for every inch of diameter of the largest shell.
By those standards, spectators should have been at least 350 feet away from the show put on by Bethpage, N.Y.-based Bay Fireworks, said Ventura County Fire Department Deputy Chief Mike LaPlant.
Making sure that guideline was followed will be an important aspect of the investigation, though all of the injuries were at or beyond 350 feet, LaPlant said.
"We're just confirming what we feel to be true, which is that the distances were either at or beyond the normal distances, the prescribed distances, for that sized shell," LaPlant said.
The company said it regretted that spectators were injured and that it planned to publicly release the results of a thorough investigation.
Of the victims, all but three had been treated and released by late Friday, hospital officials said.
One patient was being treated by specialists at Grossman Burn Center and two other adults remained hospitalized in fair condition, said Kim Milstein, chief executive of Simi Valley Hospital.
Although fireworks accidents at professional shows are rare, they are not unheard of. The blast in Simi Valley was itself among several mishaps nationwide Thursday, including errant explosions injuring workers at shows in nearby Ojai, as well as North Myrtle Beach, S.C., and a fireworks barge that caught fire in a Montana lake at the start of the grand finale.
In 2008 in New York, fireworks shells exploded on the ground and another one launched into the crowd, injuring five people at an event that also involved Bay Fireworks.