Daredevils kicked off the running of the bulls Monday with a long, messy and particularly dangerous dash through the streets of Pamplona, with 13 people injured but none gored, officials said.
The half-mile sprint through cobblestone streets turned chaotic because the pack of six half-ton beasts became separated early in the route after plowing into a crowd of people, some of them spectators.
Some of the bulls fell and two ended up running on their own. One of those became disoriented, trying several times to turn around and go back toward the starting point. But herders waving sticks eventually guided it to the bull ring where the course ends.
Inside the ring one black bull fell down and stayed there for nearly a minute, as jubilant runners scampered about.
The Spanish Red Cross said 13 people were injured, with head, rib or other injuries from falling or getting trampled.
It said six were Spanish and the rest were from the United States, Australia, New Zealand, Britain, Romania and South Korea. No names were given. The worst off was a 37-year-old Spaniard with fractured ribs and a ruptured spleen, the Red Cross said.
The whole run took just over four minutes, which is a bit slow by the standards of Pamplona's Fiesta de San Fermin, as the festival is known.
It was the first of eight scheduled runs. The most crowded ones will be next weekend, when the throngs of thrill-seekers will swell dramatically as people pour into Pamplona from out of town for two days of revelry and Adrenalin.
The fact that this year's festival began on a Monday meant a lighter turnout.
"There were a few tense moments, but I think everything went quite well. There were fewer people than at other times," said 29-year-old runner Aritz Lopez, from Bilbao.
Many of Monday's participants wore traditional white trousers and shirts and red kerchiefs around their necks. They carried rolled-up newspapers -- a tool for gauging how far away a charging bull is.
Before the sprint, local runners paid tribute to a beloved Pamplona native, Inaki Ochoa de Olza, a veteran mountain climber who died in the Himalayas in May. He also was a regular runner at San Fermin.
The running of the bulls became world famous with the publication of Ernest Hemingway's 1926 novel "The Sun Also Rises" and also is known for its all-night street parties.
Since record-keeping began in 1924, 14 runners have died.
The last fatality from a goring was a 22-year-old American, Matthew Tassio, in 1995. In 2003, a 63-year-old Pamplona native, Fermin Etxeberri, was trampled in the head by a bull and died after spending several months in a coma.
On Sunday a young man died after falling 30 yards from an ancient wall that encircles the old quarter of Pamplona. Authorities identified him Monday as Aidan Holly, a 23-year-old from Ireland, and quoted friends as saying he had been drinking.