Three days into the annual running of the bulls in Pamplona, Spain, and some participants have suffered injuries.

One American man was pierced in the abdomen and another from Greece sustained facial injuries, particularly in the nose, according to a CNN report.

So far, 20 runners have been hurt. The other 18 injuries resulted from falls or collisions.

The running takes place during eight consecutive days, July 7 to 14, starting at 8 a.m., Spanish time, each day.

No fatal injuries have been reported.