Hundreds of young Dutch men and women turned Amsterdam's central Dam square into a blizzard of red gloop as they pelted each other mercilessly with over-ripe tomatoes.

In theory, the event was set up as a protest against Russian sanctions blocking imports of European fresh produce. In practice, most participants turned out to experience the joy of smacking a loved one - or total stranger - with tomato pulp at close range.

The idea was lifted from Spain's famed annual La Tomatina festival in Bunol. Organiser Joep Verbunt said proceeds will go to tomato growers hurt by the sanctions - with the leftover tomato sludge cleaned and sent to a biogas production facility.