The bull, Vulcano, which weighed well over 1,000 pounds, was eventually killed by one of a group of 40 participants who had registered for the Toro de Vega in Tordesillas, El Pais reported.
Mayor Jose Antonio Gonzalez told the newspaper Pedro Armestre, a photographer who was covering the event for Agence France Presse, was taken to a hospital in Valladolid.
A colleague said Armestre was attempting to shelter behind a pine tree when the bull gored him.
Gonzalez said the event, which has been held for centuries, attracted about 50,000 people to the town of 9,000 -- including about 100 who were there for a protest against it.
David Rodriguez, an unemployed construction worker who lives in Tordesillas, won the competition to inflict the fatal injury on the bull.
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