The bulls from the Victoriano del Rio ranch completed the fastest run so far at this year's San Fermin festival in the northern Spanish city of Pamplona, creating dangerous conditions that resulted in several runners being trampled.
The bulls needed just two minutes and 11 seconds to cover the 850-meter (approximately half-mile) distance from the Santo Domingo stockyard to the bullring.
The animals stayed in a tight herd as they ran through the streets of Pamplona, a normally quiet town that welcomes hundreds of thousands of Spanish and international visitors annually during the festival, catching up quickly with the runners and overtaking them, sending many people falling to the ground.
No one, however, was gored during the speedy run, which was the fourth of the festival.
The San Fermin festival, which started on Saturday and ends on July 14, is known around the world for its running of the bulls and street revelry.
Hundreds of events have been scheduled for this edition of the festival.
The festival, begun about 400 years ago, was popularized by Ernest Hemingway in his 1926 novel "The Sun Also Rises."
The run through the medieval streets of Pamplona's historic center, usually lasting four minutes, is especially dangerous because some runners take part in the event after all-night drinking binges.
This makes runners reckless and more likely to get too close to the bulls, which weigh in excess of 500 kilos (1,100 pounds).
The running of the bulls is monitored by experts who control the route and try to prevent accidents, but, inevitably, runners fall, suffer cuts and bruises, and are even gored by the animals.
Four people were gored at the 2012 San Fermin festival, while 41 were transported to hospitals and 388 others were treated at the scene by paramedics for a variety of injuries. EFE