Dozens of Fourth of July celebrants were injured Thursday night in a "fireworks mishap" at a Simi Valley, Calif., park, authorities said.
The injury count changed multiple times over the course of a quickly developing breaking news story. As of 11:30 p.m., 28 people were reported injured, Ventura County Fire Department spokesman Mike Lindberry told reporters at the scene.
Of those 28 victims, 20 were transported to the hospital -- 16 suffered minor injuries, four suffered moderate to severe injuries, Lindberry said. Eight people were treated and released on scene.
Initial injury counts reported 20 people were hurt then that figure was revised to 14 before Lindberry detailed those hurt in the explosion.
Between 8,000 and 10,000 people were expected to attend the Independence Day celebration Thursday night.
Witnesses said the professional fireworks show lasted just a few minutes before the huge explosion went off.
"We saw about three minutes of the show. There was some that went up in the area and everything just kind of scattered outwards and then everybody just started running," a witness told NBC4.
"Everything exploded and parts came flying everywhere,” another witness told NBC4. “People were running everywhere. So, it was pretty scary."
It happened about 9:20 p.m. at Rancho Santa Susana Community Center and Park (map), said Cmdr. John Parks, a watch commander for the Simi Valley Police Department.
Parks called the detonation a "fireworks mishap." He said initial information suggested the explosion was accidental.
Emergency medical and fire personnel were already at the park to monitor the fireworks show, so the victims were attended to quickly, Parks said.
The extent of the victims' injuries was not immediately known. It also was unclear how many of the 14 injured were transported to the hospital.
After the blast, park was evacuated, Parks said. Aerial footage showed dozens of people lingering on the outskirts of the scene and near the triage area set up on the grass, pictured below.
