The incident happened around 10:30 a.m. during an annual open house at the Rancho Cucamonga Police Department, the department said in a news release. The event included displays, food and a children’s bounce house.
At some point, a helicopter with the San Bernardino County Sheriff's Department was landing on the rooftop helipad of the police station and "the downdraft from the helicopter caused several canopies and the bounce house to lift off the ground," police said.
Video obtained by FOX11 Los Angeles shows the moment the sheriff's helicopter flies over the event and kicks up wind that appears to blow over several canopies and knock several people to the ground. As the camera pans to the left, the bounce house can be seen after apparently landing back on the ground.
Three children inside the bounce house were injured and taken to a hospital for treatment. No further details were immediately available on the children’s conditions. Police said a fourth child inside the bounce house didn’t suffer any injuries.
The sheriff’s department is investigating the incident alongside the Federal Aviation Administration.
No further details were immediately released.