Animal rights activists painted the Spanish city of Pamplona red today during a protest against bullfighting.

Hundreds of demonstrators wearing only black underwear and fake bull horns gathered in the city centre on Wednesday (5 July), protesting against the dangerous bull runs that will be held during Pamplona's famed San Fermín festival next week.

With the words "Stop bullfighting" emblazoned across their chests, protesters broke 'banderillas' - barbed sticks used during bullfighting - covering themselves with red powder and filling the air with 'blood'.

Thousands of people travel to Pamplona each year to witness the famous 'Running of the Bulls' event where people run the risk of being trampled as they lead the animals to the bullring. There the bulls are stabbed and taunted by a group of matadors carrying daggers and the harpoon-like 'banderillas.' The animals are eventually killed by an executioner who cuts their spinal cord.

Animal rights groups describe the tradition, which dates back to the Middle Ages, as "archaic" and a "cruel and barbaric practice".

"Bullfighting has no place in a civilised society," Elisa Allen, the director of animal rights group PETA, said. "We're urging Pamplona to join the more than 100 Spanish cities and towns that have banned the bloody spectacle."

Catalonia's ban on bullfighting was annulled by Spain's highest court last year. It ruled that the region was not constitutionally entitled to fully ban such fights and said the tradition was part of Spain's "cultural heritage." Bullfighting has been banned on the Canary Islands and several other municipalities.

Last month veteran Spanish bullfighter, Ivan Fandino, was gored to death by a bull during a festival in France.