It's the final day of Pamplona's bull run... and it's as though one bull had a personal vendetta against the whole thing.

An enormous bull broke away from the pack and pushed around his weight.

Three runners were gored.

The medical report says one was seriously injured, after he was gored in the stomach, thorax and left thigh.

(SOUNDBITE) (English) RUNNER FROM TEXAS, UNITED STATES LIVING IN VALLADOLID, SPAIN, LARRY BELCHER, SAYING:

"Well this morning it was rather dangerous and we had the 'suelto,' the loose bull, the one that was separated from the herd down at the curve, and so it was dangerous. It's a different sensation than just the pure floating along if you are running well, it was dangerous this morning, that's the situation, nothing more. I am accustomed to bulls, I used to ride in the rodeo, so I rode bulls, now I'm a professor here at the university."

Some fearless participants tried to distract the bull and eventually herded it into the r