No participants suffered serious injuries here Wednesday in the second-to-last running of the bulls of this year's San Fermin festival.

The run featuring bulls from the El Pilar estate lasted two minutes and 15 seconds, making it the fastest so far at this year's celebration, held annually in this northern Spanish city.

It turned dangerous when one of the six bulls broke free from the herd at the end of the first stretch, knocking down any runner that got in his way en route to the bullring.

According to initial medical reports, at least seven runners received hospital treatment after the run but none was listed in serious condition.

The nine-day San Fermin festival got under way on July 6 with the traditional firing of a rocket in front of Pamplona city hall amid the shouts of thousands of people, many of them visitors from around the world.

A total of 2.7 million euros ($3.8 million) was budgeted this year for the festival, whose program includes 342 music shows, 137 family related activities and 33 events involving bulls.

The runs in Pamplona are tension- and emotion-filled and occasionally result in tragedy, with 15 runners having been killed since statistics began to be kept in the early 20th century and many others having suffered gorings and other injuries.

The half-mile run to the bull ring is especially dangerous because some people take part in the event after all-night drinking binges, which makes them reckless and more likely to get too close to animals that 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.

As many as 1 million visitors from around the world descend on Pamplona during the festival - many of them Americans but also Frenchmen, Britons, Italians, Germans and Latin Americans.

The festival, begun about 400 years ago, was popularized by Ernest Hemingway in his 1926 novel "The Sun Also Rises."