Thousands of thrill-seekers dashed ahead of six fighting bulls in the streets of the northern Spanish city of Pamplona on Thursday in a fast first running of the bulls in this year's San Fermin festival. No one was gored, but four people were taken to Navarre Hospital with injuries -- one with fractured ribs -- sustained during a sprint where the six guiding steers stole the show from the charging bulls from the Torrestrella ranch, which is famed for producing dangerous bulls. Revelers take part in the "Chupinazo," the official opening of the 2011 San Fermin festival, Wednesday, July 6, 2011 in Pamplona, Spain. Revelers hold up traditional red neckties as tens of thousands of people pack Pamplona's main square in Pamplona, Spain, Wednesday July 6, 2011 to celebrate the start of Spain's most famous bull-running festival with the annual launch of the "Chupinazo" rocket. Revelers are surprised by an angry leading ox, used to drive the fighting bulls during the running of the bulls at the San Fermin festival on Thursday, July 7, 2011.