Doctors treated the injured at the hospital. Among those receiving medical treatment was a 20-year-old Canadian man with mild traumatic injuries from being trampled, the officials from the Navarra regional government said in a statement.
The other men were of Spanish nationality and included a 38-year-old who was gored and a 40-year-old who sustained serious traumatic injuries.
The BBC reported that five were injured.
Overnight rain had made the route’s already-narrow cobbled streets more slippery than usual, adding to the danger in the traditional race.
Many runners were trampled early on, and others were also injured as the 12 animals entered Pamplona’s bullring, but no information was available about the extent of their injuries.
The runners completed the course, with bulls weighing 1,100 to 1,400 pounds, each in two minutes and 37 seconds.
The nine-day San Fermin fiesta was popularized by Nobel Literature laureate Ernest Hemingway.
The last person to die at the festival was gored in the neck in 2009, according to the BBC.
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