Thousands of Spaniards and foreigners jammed a historic city plaza in Pamplona as a firework blasted off to launch this year's annual San Fermin bull-running festival.

The adrenaline-charged run - where six fighting bulls are released to chase the runners down a narrow street - took two minutes and twenty three seconds.

An Australian tourist and a Spanish runner were slightly injured during the first bull run of the nine-day festivities which attract large numbers of foreign participants and tourists each year.

Each year. the festival of San Fermin officially begins at midday on July 6 every year and the first bull run takes place the following day.

The race starts at 8am every morning from July 7 to 14. The run stretches from the corral at Santo Domingo where the bulls are kept, to the bullring where they will fight that same afternoon.

Each day six fighting bulls run the route, as well as two herds of bullocks.

The length of the run is roughly 846m and the average time of the run from start to finish is about three minutes.

The festival dates back to the 13th century.