San Diego building inspectors are still trying to determine how a stairwell at an indoor gym in the Barrio Logan community collapsed Saturday night, injuring more than two dozen people, most of whom were children.
The incident occurred about 7:40 p.m. at Vault PK on Main Street near Sigsbee Street, a large warehouse that shares space with a paintball facility and Crossfit gym, officials said. Vault PK specializes in parkour, a physically demanding sport that requires athletes to navigate military-style obstacle courses.
The accident occurred in the midst of an open gym night for ages 5 to 14, according to the gym's website.
Twenty-one children and two adults, ages 72 and 46, were taken to various hospitals with moderate to minor injuries. Three or four of the victims suffered spinal injuries when a 10-by-30-foot wooden platform collapsed on them, said San Diego Fire-Rescue Deputy Chief Steve Wright.
"It could have been much worse," he said.
The patients were taken to Rady Children's Hospital, Scripps Mercy, Sharp and UC San Diego Medical Center, Wright said. There were additional people with minor injuries who left on their own, rather than by ambulance, he said.
Zachary Smith, who was there with his son for a birthday party, said he was standing on the platform, which he described as a viewing area, along with about 30 others, when the staircase below collapsed, causing the platform to topple. He fell onto a young girl but neither was seriously hurt, he said. Smith's son was also on the platform at the time but suffered only minor scrapes.
"It was a freak accident," Smith said, adding that he believes it could have been avoided because the structure did not appear to be built to hold such weight.
Smith said the collapse sparked chaos with parents scrambling to find their children amid the debris.
One parent who did not provide his name said the stairwell collapsed after so many children were running up and down to get pizza. Many parents were likely using a Groupon that had been offered for the evening's open gym, he said.
His 11-year-old son was not injured. He said he thought 40 to 50 people would show up for the evening "but there were probably three times that."
Joe Saari said that when he and his wife dropped off their two children for a few hours, there were 100 to 150 kids at the warehouse, which includes trampolines and bouncy houses. The couple were heading back home to Chula Vista when one of their children called and said there had been an accident.
His kids suffered minor scrapes, Saari said.
A woman said her 13-year-old son was unhurt but "devastated" by the traumatic scene. She said she went inside to get him out and saw one child with blood all over his face.
At Total Combat Paintball, which shares the facility with the gym, the day began normally before the accident.
"It was business as usual until we heard a loud boom come from the gym, at which point our staff and some customers ran over to the gym to help any way we could," the company said in a statement.
An hour after the incident, the street around the warehouse was lined with ambulances and fire trucks, some leaving with victims inside and yet still more emergency vehicles arriving. One woman stood on the sidewalk, holding an ice pack over one eye while she talked on her cellphone.
Children huddled nearby in groups, some with parents. San Diego police corralled the children and matched them up with parents as they arrived.
City building inspectors were on the scene Sunday to investigate the cause of the collapse.
3:20 p.m.: This article was updated with more comments from witnesses and fire officials.
9 a.m., Nov. 12: This article was updated with new comments from witnesses and fire officials.
11:05 p.m.: This article was updated with new information from San Diego fire officials.
10:30 p.m.: This article was updated with new information from San Diego fire officials.