Three individuals have been gutted during the principal bull keep running at the yearly San Fermín celebration in Pamplona.
Authorities state those with butchery wounds are two US natives, matured 23 and 46, and a Spaniard.
Two others were taken to emergency clinic with head wounds and a sum of 48 others were treated by the Red Cross.
Further runs will occur each morning through the northern Spanish city’s restricted boulevards until next Sunday.
Those participating, most wearing white with red scarves, stuffed into the 850m (2790ft) course – which leads downhill to the town’s bull ring.
Six bulls are discharged day by day, alongside cows, before later confronting proficient bullfighters in open bull battles.
Misuse challenges dominate bull run celebration
Weighing up the dangers of running with the bulls
Wounds at the occasion are normal and at any rate 16 individuals have kicked the bucket partaking since 1910, when records started.
The last individual to kick the bucket at the celebration, Daniel Jimeno Romero, was gutted in the neck in 2009 during the fourth keep running of the celebration.