Shocking footage has shown the moment a bull breaks through a fence before killing a 74-year-old man.
A four-year-old girl was also injured after the horrific incident in Pantoja, Toledo, about 50 minutes southwest of the Spanish capital Madrid.
The bull had to be shot by police officers to ensure no more locals were injured.
Barriers and fences had been put up in certain areas while bulls were being run through the town.
But a bull managed to break through the fence where locals were stood watching.
Footage shared on X shows the animal throwing someone in the air the moment it breached the barriers.
The mayor of Pantoja, Julian Torrejon, confirmed that a young four-year-old suffered some scratches, but her grandparents were hospitalised.
An 84-year-old man and a 55-year-old woman were also among the injured.
Mr Torrejon said the town was "devastated" after the tragic death.
He added: "Everything is in order and we have our insurance and our permits from the Junta and the Provincial Council.
"We had been reviewing the route minutes before and everything was correct."
A police investigation has been opened, as is routine.
The bull run was one of several events being held to celebrate the Patron Saint Festivities in honour of Santa Barbara.
The town celebrates the occasion every year between September 20 and September 28.
The events have now been suspended after the man's death.
Injuries such as these are common due to the country's long tradition of holding Running of the Bulls events. However, it is unusual for a spectator at a bull event to be injured in this way.
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