Platform Collapse at Parkour Gym Injures 21 Kids

San Diego's Vault PK is usually packed with bouncing and flipping children on Saturday evenings, when it hosts a "kids' night out" for budding athletes ages 5 to 14.

This past weekend was especially packed, parents said, as people cashed in a Groupon that got three kids into the parkour facility's open gym for just $30. The three-hour event is supervised by Vault PK staff members, so it doubles as a parents' night out too.

Some of the nearly 150 children present played on the America Ninja Warrior-styled obstacle course, but roughly a third had gathered on a 10--by-30-foot wooden viewing platform, parent Cory Brizendine told San Diego ABC-affiliate KGTV. That's where the pizza was being served.

"Once the majority of kids got up there, the whole platform collapsed," he said.

The crumbling structure took a connected staircase with it, authorities and witnesses told reporters. Wood and little bodies tumbled to the ground - on top of children playing below - forming a heap of injured kids and gym equipment.

"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," a spokesperson for Total Combat Paintball posted on Facebook. The business shares a building with the parkour facility and a cross-fit gym.

Zachary Smith, who was at Vault PK with his son for a birthday party, told the Los Angeles Times he was standing on the platform along with more than 30 others. Smith fell onto a young girl but neither was seriously injured, he said. Smith's son was also on the platform at the time but suffered only minor scrapes.

"It was a freak accident," Smith told the newspaper. He said it didn't appear the platform could hold so much weight.

No one answered the gym phone on Sunday afternoon. A recording said classes and birthday parties were "closed until further notice."

In all, 21 children and two adults, ages 72 and 46, were rushed to San Diego-area hospitals with moderate or minor injures, said San Diego Fire-Rescue Deputy Chief Steve Wright. At least three had spinal injuries.

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