A fifth child has died in a tragic accident involving an inflatable jumping castle at a primary school in Tasmania.

Two boys, two girls, and an unidentified child were killed after they fell from the castle which had been lifted by a gust of wind up to 10 metres into the air.

Four other children remain in a critical condition and one is in a serious condition.

They were celebrating the last day of the school year.

Kidsafe WA Manager of Playground Advisory Service, Tracy Blaszkow, says the incident in extremely rare.

“It is one of those freak events that’s happened and it’s going to be very hard to deal with for the families and the children and the emergency people,” she said.

In WA, anyone is able to hire a bouncy castle for an event.

“You just have to ensure you are dealing with an approved provider that can set up amuzement devices correctly. They need to be set up and anchored securely into the ground and they need to be using the anchor points according to manufaturer instructions,” Ms Blaszkow told Perth LIVE.

Police say an investigation is underway, with the coroner having already inspected the site.

It will be conducted in conjunction with WorkSafe Tasmania.

That report will then be handed to the coroner, who will begin an inquest into the tragedy.

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