PAMPLONA, Spain (AP) — Authorities say four runners have been sent to hospital after being knocked over or falling during the third day of bull races at Spain's annual San Fermin festival in Pamplona.

Tomas Belzunegui, a spokesman with Navarra's provincial hospital, tells reporters that two of the injured suffered head injuries while the others were severely bruised.

Monday's run with famously fierce bulls from the Cebada Gago ranch left participants scrambling franticly to escape the beasts as they accompanied them to the city's bullring. The animals broke up in two separate groups in a race that lasted a mere 2 minutes and 33 seconds.

Falls or trampling by the bulls cause most injuries. Some runners are occasionally gored along the 930-yard (850-meter) route, immortalized in Ernest Hemingway's 1926 novel "The Sun Also Rises."