Thousands of revellers descended on the Spanish town of Buñol on Wednesday for La Tomatina, hurling up to 165 tonnes of overripe tomatoes at each other in just over an hour.

Trucks loaded with tomatoes ploughed slowly through the crowd as people in the cargo beds pelted those below, who threw them straight back. White shirts turned pink within minutes while residents doused participants with water from balconies. Buildings along the route were covered with tarpaulins beforehand.

More than 20,000 people were expected this year. Spanish news agency EFE reports that roughly 40% of participants over the past three years have come from outside Spain, with a marked rise in visitors from India since the 2011 Bollywood film "Zindagi Na Milegi Dobara" recreated the festival.

Held on the last Wednesday of August, La Tomatina dates back to a street brawl in 1945. There is one rule: squash the tomato before you throw it.