The weather was relatively calm on Saturday afternoon when a South Carolina church was holding its annual spring carnival that usually features inflatables, games and food.

But about an hour into the event, which was held outside the church, an unexpected wind gust — sort of like a mini-tornado — started swirling around, gathering leaves and dirt along the way. At one point, it appeared to have dissipated, but then it picked up speed and lifted an inflatable slide and a bounce house into the air, Ricky Reed, battalion chief for the Taylors Fire Department, told The Washington Post.

The slide was unoccupied, authorities said, but five children were inside the bounce house. All were injured; two of whom were seriously hurt after they fell out while the bounce house was airborne.

Reed said the fire department received a call about 2 p.m. regarding children falling out of a float outside the Springwell Church in Taylors, just outside Greenville, S.C.

“It was very chaotic when we first arrived just because of the sheer number of people and everybody being upset,” Reed said.

Kellie Owens, a witness, said she heard the children screaming.

“All you can hear is just pure terror,” she told WSPA.

In a Facebook post Saturday, Springwell Church said the incident was out of anyone’s control.

“We are saddened for those who were injured during the unfortunate accident today,” the church said.

Two children remained hospitalized Sunday, the church said. Both are now in stable condition.

Reed said it’s highly unusual for wind gusts to suddenly swoop in during a relatively calm day. The inflatables were secured to the ground, but witnesses told authorities that the winds were strong enough to lift the bounce house about 20 to 30 feet into the air, and to send the slide toward the road, Reed said. Some witnesses also said that both inflatables struck power lines.

“It’s kind of like, you know, like in the desert, where they have one of those dust storms,” Reed said. “We’ve heard so many different stories. We take everything as seriously as we can, and we take the worst of the stories and go with that because we want to be prepared for the worst.”

Reed said the local power company had installed safeguards so that the grid system would automatically shut off the power lines in the event of an accident.

“If those safeguards weren’t in place, we probably would’ve had several fatalities just from the sheer number of people trying to help the children out,” he said.

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