A 23-year-old Australian woman was gored in the chest on the final day of Spain's San Fermin week-long bull-running festival, where bulls chase people down the cobbled streets of Pamplona.

The woman, who was only identified by her initials J.E, was taken to hospital for surgery and was in a "very serious" condition, local authorities said.

She suffered several fractured ribs and damage to her right lung, according to a medical report released by authorities.

Four more people injured in Sunday's bull run were taken to hospital but it was too soon to say how serious their injuries were, officials said.

As on each of the last eight mornings, a firework set off Sunday's mad dash through Pamplona's cobbled streets of six bulls and six steers as well as hundreds of thrill-seekers, many dressed in traditional white with a red neckerchief.

The animals will be killed by matadors in the final bullfight of the nine-day San Fermin festival.

The early morning bull runs are the highlight of the fiesta, which was immortalised in Ernest Hemingway's classic 1926 novel The Sun Also Rises and now draws hundreds of thousands of tourists each year.

Sorry, this video has expired Man gored by bull during Pamplona run.

On Saturday, more than 20 people were hospitalised, including a 19-year-old Spaniard who was left in a "very serious" condition.

Runners fell into a bloody human pile-up that was trampled by the half-tonne bulls at the entrance to the bullring, where the run ends.

On Friday, three men were gored, including a 20-year-old American who had his spleen removed.

A total of 50 daredevils were hospitalised during the annual festival.

Each year, hundreds of people are treated by medics and the Red Cross at the scene for cuts and scrapes without being hospitalised.

Fifteen people have been killed in the bull runs since records began in 1911. The most recent death was four years ago when a bull gored a 27-year-old Spaniard in the neck, heart and lungs.

Reuters/AFP