34 people were arrested in Haren, Netherlands, on Friday night (21 September 2012), after thousands of people turned up for a young woman's 16th birthday party inadvertently publicised on Facebook. The party was cancelled after media publicity and 'going viral', and hundreds of riot police were deployed in the small Dutch town. Youths clashed with police, who fired tear gas to disperse the crowds. A supermarket was looted. In the lead up to the weekend, people had begun making 'Project X - Haren' t-shirts, a reference to the American film about a teengage party that ends in chaos.
On the same night in Madrid, around 1,000 people who could not get into the MTV Beach festival rioted, clashing with police and setting up burning barricades in the streets. Plastic bullets were fired by police.