Four children hospitalised after powerful wind gust blew jumping castle away

A freak accident involving a jumping castle in Sydney's south-west has left four children in hospital.

A powerful gust of wind blew the jumping castle from a backyard in Kelvin Park Drive, Bringelly, about 9.30am.

A group of boys aged nine to 13 were inside at the time.

The device detached and blew over a fence next to where it was tethered in Kelvin Park Drive, Bradfield near Liverpool.

The device detached and blew over a fence next to where it was tethered.

Three nine-year-olds, a 12-year-old, and a 13-year-old were assessed by NSW Ambulance paramedics for non-life-threatening injuries.

"Four of those patients were driven to Westmead Hospital in a stable condition and one patient was not transported," NSW Ambulance's Tom Burness said.

The Bureau of Meteorology said wind gusts of up to 74km/h had been recorded in nearby Canterbury, and 89km/h at Sydney Airport.

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