A child has died after being thrown from an inflatable bouncy castle which exploded on a beach.

Eye-witnesses described their horror at watching the little girl in a pink dress, believed to be just four years old, thrown 20 feet into the air when the bouncy castle exploded with a loud bang, reports Telegraph UK.

The Bounce About play area on Gorleston beach, just south of Great Yarmouth in Norfolk, England, was cordoned off on Sunday and a police investigation is now underway.

The play area’s owner Curt Johnson, who was not at the scene, said the trampoline had exploded “because of the heat”.

Norfolk police were called to the scene at 11.15am, following reports that a child had been “thrown from a bouncy castle.”

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Ambulance crews arrived within four minutes and the child, who was in cardiac arrest, received CPR at the scene.

She was taken to James Paget Hospital two miles away but died shortly afterwards. Her family has been informed.

Kara Longshaw, an eyewitness, said: “Just seen the most horrific thing in my life. A bouncy castle exploded at the beach and the child on it was catapulted about 20ft into the air. Please say a prayer for the four-year-old being rushed to hospital after 15 minutes of CPR.”