An air ambulance has been witnessed landing at the theme park.
A boy has been airlifted to hospital, BBC reports.
There are unconfirmed reports a child fell from a height while on a ride.
Witness Simon Moran tweeted: “Just saw a kid fall off the Twister rollercoaster at #Lightwatervalley”
He added: “Fell face down about 20/30 feet to ground.”
Martin Priestley posted on Facebook: “Air ambulance at the sonic ride someone just been thrown out the ride.”
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