Half-tonne fighting bulls trampled and knocked over runners on a break-neck bull run in Spain's San Fermin festival on Tuesday, injuring five men, officials said.
The five Spaniards aged between 19 and 47 suffered bruises to their shoulders, legs, ankles and head in a dash through the northern city of Pamplona, regional health authorities said.
They were taken to hospital for treatment and have all been discharged.
The six bulls from the El Pilar ranch, known for their speed, took just two minutes and 22 seconds to cover the 850-metre (2,800-foot) course, the fastest time of the four daily bull runs held so far this year.
"They just wooshed by, I barely got a glimpse of the bulls," said James Matiesen, a 28-year-old student from California who watched the run from behind a wooden barrier set up along the route.
A brown bull pulled away from the pack and was the first to charge into the city's bull ring where it was quickly followed by the rest of the beasts.
Runners wearing white clothes and red handkerchiefs around their necks struggled to remain for long in front of the bulls because of the speed which the animals thundered along the course.
One bull stepped on a runner who had fallen in the middle of the course but the man was seen to walk away on his own.
"You really have to control your nerves, especially at the beginning when it is really crowded and people are pushing you," said Jonathan Llanos, a 23-year-old immigrant from Ecuador who came from Zaragoza to run with the bulls.
Runners jogged on the spot and did stretching excercises before the start of the fourth bull run of this year's San Fermin festival as they stood behind a line of police.
One man prayed and kissed a crucifix he wore around his neck minutes before the rocket was fired to signal that the bulls had been released from their holding pen.
None of the bulls in Tuesday's run tried to gore the runners, prompting San Fermin organisers to describe the pack as "very well-behaved".
"It is very beautiful, I enjoyed it a great deal. I love bulls," said Inaki Becerra, a 58-year-old businessman from San Sebastian who watched the run from an apartment balcony and who used to run with the bulls when he was younger.
A giant bull skewered two Britons and an American, none seriously, with its horns during Monday's run after it broke free from the pack and charged a crowd of runners cowering by the barriers.
The two British men, aged 20 and 29, were gored in their legs and remain in hospital.
Last year 20,500 people joined the festival's eight daily bull runs, with nearly half of them coming from abroad, mostly the United States, Australia and Britain, according to Pamplona city hall.
Three years ago, a bull gored a 27-year-old Spaniard to death, piercing his neck, heart and lungs with its horns in front of hordes of tourists.
Pamplona officials expect about half a million people will flock to the city of 200,000 during the July 6-14 festival, which dates back to medieval times.
The San Fermin festival was made famous worldwide by Ernest Hemingway's 1926 novel "The Sun Also Rises" about a group of American and British expatriates who travel from Paris to Pamplona to watch the running of the bulls.