CBS News Reporter Rick Salinger was there as the mob of more than 2,000 people took off through the streets, with the bulls fast on their heels.
Four people were treated at a hospital, including 23-year-old Canadian Jordan Bayne, who was kicked in the head by a bull, and 40-year-old American Montgomery Doiel, who was jabbed in his buttocks. The Denver resident's wound required stitches.
"For three minutes I thought of nothing but my life," said David Silver, 24, of Bellmore, N.Y. "Two bulls skidded to within about two feet of me, and I thought, 'OK, this is it."
Skies were overcast, the air was chilly and the cobblestone streets on the 900-yard course were slippery with dew, alcohol and trash from parties that rage during the eight-day festival.
Making the run even more dangerous, the number of daredevil runners was up significantly from Friday, leaving the narrow streets clogged with dozens of people tripping over each other as they tried to dodge the bulls.
No one keeps track of how many people run, but locals say the number jumps on weekends as people flock to Pamplona. On weekdays, an estimated 2,000 people join in the run, but Saturday the crowd was clearly much bigger.
Toward the end of the dash, so many runners packed Estafeta Street that two of the bulls slowed down to a trot.
Some people taunted the bulls, slapping them and getting close to the horns. Others tried to hang on to the bulls. Besides being dangerous, that is considered insulting to the bull.
"Today's run was disgraceful," said Javier Solano, a veteran San Fermin commentator for Spanish state television.
Normally six bulls take part but veterinarians disqualified one on Friday. They are accompanied by steers that are supposed to guide the bulls and keep them more or less in a cluster.
In a run that takes about three minutes, the bulls charge from a corral to a bullring where they face a matador in the afternoon.
The centuries-old festival became famous following the 1926 publication of Ernest Hemingway's novel "The Sun Also Rises."
Since record-keeping began in 1924, 13 runners have been killed and more than 200 injured by the bulls. The last fatality was an American in 1995, the first death since 1980.
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