An Australian man was gored in the leg and three other people were injured at the San Fermin festival in Pamplona.

The second of eight runs at Spain's most famous summer festival featured bulls known for being fast and prone to poking people with their horns.

Navarra hospital and the San Fermin press office reported four people were hospitalised.

Three had injuries to the face or back, suffered either in falls or because they were trampled. The 24-year-old Australian man who was gored had taunted a brown bull from close up in the bullring that marks the end of the sprint.

The man waved his arms at the 550kg (1,200lb) animal, then slipped and fell. The bull pinned him to the ground and gored him, piercing a vein, the press office said. It said his life was not in danger.

Friday's run was fast for the most part because the six fighting bulls and six steers meant to keep them in a pack managed to stay together for much of the 850m course.

But the brown bull that attacked at the end had separated from the pack about halfway through the run. A bull that is isolated can get disoriented and nervous and even start running the wrong way.

When bulls finish the run by trotting into the ring, runners are supposed to keep clear and let handlers with capes or long, thin sticks guide animals into stalls, as crowds in the stands cheer.

But the Australian committed the San Fermin faux pas of getting up close to the bull and teasing it by waving his arms.

Another of the injured was a man who fell to the ground early in the run and saw virtually the entire pack of bulls and steers run over him.

The festival has six more runs to go. The Saturday and Sunday runs are usually the most dangerous because the crowd of runners that come from around the world is larger.