At least 28 fans have been injured in a multi-car crash during Daytona Nascar race in Florida.

Large pieces of debris – including a tyre – flew into the spectator stands when one of the cars hit a fence separating the track from the seats.

Race officials said 14 people had to be treated in hospital.

The accident happened on the eve of the Dayton 500 – one of the most famous Nascar events. The officials later said the main race would go ahead.

The crash happened on the last lap of the second-tier race in Daytona as the cars approached the chequered flag.

The driver in the leading car apparently tried to stop others overtaking him by moving sideways. One vehicle then hit another and flew into the fence.

At least 28 fans have been injured in a multi-car crash during Daytona Nascar race in Florida

Pieces of debris were thrown into the stands and smoke from burning engines clouded the area.

“It was freaky,” fan Rick Harpster told the Associated Press news agency.

“I saw a tyre fly straight over the fence into the stands. I knew it was going to be severe.”

Another eyewitness described people running and seeing a girl completely covered in engine oil.

The race was earlier stopped for about 20 minutes following a separate accident in which one driver was injured.

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