Running of the bulls: Four injured during annual San Fermin festival in Pamplona

Local authorities confirmed that all four people were Spaniards at the event which attracts hoards of tourists

Revelers run ahead of fighting bulls on Estafeta corner during the running of the bulls at the San Fermin festival, in Pamplona, Spain (AP Photo/Alvaro Barrientos)

One person was gored in the thigh and three others suffered injuries during the annual running of the bull in the northern Spanish city of Pamplona on Monday morning.

Thousands of thrill-seekers dressed in white with red neckerchiefs raced with bulls during the event, along a narrow 930-yard (850-meter) course from a holding pen to the city bull ring.

Many spectators stayed up drinking all night in bars beforehand.

Part of the annual San Fermin festival, Pamplonas runs will take place at 8 am local time every morning this week.

Monday’s run, or encierros, lasted just over two minutes.

Red Cross spokesman Jose Aldaba, confirmed that four people were taken to a city hospital with injuries sustained in the run which started at 8am.

The Navarra regional government released a statement stating that the four were Spaniards, and that none was in a serious condition.

Last week, the authority said that this year's festivities would be patrolled by 3,500 police officers to keep the adrenaline and alcohol-fuelled events as safe as possible.

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Each year, dozens of people are injured in the runs, mostly by falling over in the rush of the crowd.

Fifteen people have died from being gored by bulls since record-keeping began in 1924.

Anti-bullfighting demonstrators protest against the bulls runs (AP Photo/Alvaro Barrientos)

While the bull run made internationally famous by Ernest Hemingway in The Sun Also Rises attracts large numbers of foreign visitors, animal rights activists label the race as “unnecessary and archaic”.

On Saturday, anti-bull run demonstrators gathered ahead of the start of the festival to raise awareness to the 48 bulls that are killed each year.

The bulls, which take part each morning, are invariably killed by matadors in evening bull fights, and their meat is served up in Pamplona's restaurants.

Additional reporting by agencies