EIGHT children are being treated for “potentially serious injuries” after an inflatable slide collapsed at a fireworks funfair in the English countryside.

Surrey Police said Woking Park was evacuated as medics from at least 20 ambulances, including an air ambulance crew, treated patients on Saturday night.

The force initially said it was a collapse of a helter skelter at the fairground in Woking, but later clarified it was a “giant inflatable slide”.

South East Coast Ambulance Service said it had “multiple crews” at the scene of the “significant incident” at Woking, 40km southwest of London.

The children have a mixture of spinal and neck injuries as well as broken arms and legs, according to The Sun.

Witnesses said the children were all aged between six and 10, and had fallen about 20ft when the inflatable slide they were on collapsed at about 7.30pm local time.

“It is a terrible scene. Many of the children have got broken arms and legs and obviously terrified,” a witness said.

Police evacuated the park to allow an air ambulance to land.

The patients were being transported to “major trauma centres” in London with the help of the air ambulance, SECamb said in a statement.

An eyewitness said people panicked as police escorted thousands from the park to make way for an air ambulance to land.

One witness said he had been concerned earlier that night when he saw up to 40 children playing on the “flimsy” slide at once.

“We had been walking past the slide earlier in the night and said it looked unsafe. It looked pretty flimsy to say the least,” journalist Andy Datson, 23, said.

“There were far too many kids on it.

“It didn’t look like it could hold that many people.”

Organisers of the event said they were “shocked and distressed by events in the funfair this evening.”

Communities across Britain hold fireworks displays to mark the anniversary of Guy Fawkes’ failed 1605 plot to blow up Parliament.

The fireworks “extravaganza” was set to attract 12,000 people and had been due to start at 8pm.