This bull-breed has a total of eleven gorings over the years and its danger co-efficiency is not high (0,37 gorings per running of the bulls). However, last year the running of the bulls took longer than five minutes and there were five gorings and six other runners had to be admitted to hospital.
The main culprit for the dangerous run last year was a bull called "Ermitaño" which became detached from the rest of the pack after goring a runner in the mouth in the Mercaderes stretch. At the entrance to the bullring it caught a runner and tossed him several times causing serious injuries after imparting several awesome gorings.
You can read a bullfighting analysis in the blog of Patxi Arrizabalaga: Toros y Sanfermines.