Pamplona's running of the bulls

Revelers run on the Estafeta corner as a Jose Cebada Gago ranch bull falls, during the second running of the bulls at the San Fermin fiestas in Pamplona northern Spain, Friday, July 8, 2011.

Revelers run some seconds before Miura's ranch fighting bulls arrive, on Estafeta street during the running of the bulls at the San Fermin fiestas, in Pamplona, Spain, Sunday, July 10, 2011.

A Miura fighting bull goes around Estafeta corner at the San Fermin running of the bulls, July 10, 2011 in Pamplona, Spain. Pamplona's famous Fiesta de San Fermin was made famous by Ernest Hemingway's 1926 novel, "The Sun Also Rises."

Participants run with Miuras's fighting bulls during the fourth San Fermin Festival bull run, July 10, 2011, in Pamplona, northern Spain.

Participants run with fighting bulls during the fourth San Fermin Festival bull run, July 10, 2011, in Pamplona, northern Spain. The festival is a symbol of Spanish culture that attracts thousands of tourists to watch the bull runs despite heavy condemnation from animal rights groups.

A reveler touches the head of one Miura ranch bull during the fourth running of the bulls at the San Fermin fiestas in Pamplona, northern Spain, Sunday, July 10, 2011.

Participants run in front of a Miuras's fighting bull during the fourth San Fermin Festival bull run, July 10, 2011, in Pamplona, northern Spain.

Revelers run next to Miura's ranch fighting bulls during the running of the bulls at the San Fermin fiestas on Sunday, July 10, 2011, in Pamplona, Spain.

Runners follow the fighting bulls around Estafeta corner during San Fermin's running of the bulls on July 10, 2011 in Pamplona, Spain.

A reveler watches as his friend lies on the ground from exhaustion at the end of the fourth running of the bulls, Sunday July 10, 2011.

Spanish matador Alberto Aguilar gives a pass to a Dolores Aguirre Ybarra's bull during a bullfight of the San Fermin festival on July 9, 2011, in Pamplona, northern Spain.

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