LITTLETON, Colo. (CBS4) – Authorities are investigating how strong wind gusts tossed an inflatable bounce house 300 feet with two children inside this weekend in Jefferson County.

An 11-year-old boy remained inside until the inflatable bouncer could be secured. He was taken to the hospital with minor injuries, and his mother said he’s sore but recovering. A young girl was thrown from the house nearly immediately.

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Video shows the 800-pound bouncy house sweeping along the ground in 30 MPH gusts.

“There’s not a kid in there, there’s not a kid in there is there?” a bystander can be heard asking on the video.

The accident, the second time an inflatable has been swept away in a few weeks, raises fresh questions about their safety.

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“Once the wind gets under, it’s like a big kite,” Lance Miller, the owner of Big Air Jumpers, told CBS4. He said accidents should never happen if the devices are properly installed. His company wasn’t involved in the incident.

Miller said parents should inspect the set-up before allowing their children inside and know when to take it down: “One of the signs is the unit shaking violently back and forth, or a corner lifting up… the main issue is when air gets underneath.”

Air Bound, a Fort Collins company that provided the inflatable, said it was installed properly and that the wind gust came out of nowhere, leaving them no time to let the air out before it tumbled away.

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