Thousands of partygoers have descended upon a small town in the Netherlands this morning after a 16-year-old girl forgot to make her Facebook party invitation private.
When Merthe Weusthuis made an event for her upcoming birthday party on Facebook, the last thing she expected was for the word to spread rapidly and for 30,000 people to RSVP to the town of Haren where she lives.
Online trolls picked up on the event and ensured the word spread by creating official websites, making movie trailers and T-shirts and called the party "Project X Haren", in reference to a movie about an out-of-control party.
Merthe watched it spiral out-of-control and decided to alert police and go into hiding with her family.
Before the party was due to start, police removed street signs, closed roads and banned the sale of alcohol but it did not appear to make much of a difference.
Dutch newspaper De Telegraaf reported the situation was "completely out of hand" as police officers were being hit with bottles and stones and street signs and cars were destroyed in the town, which has a population of 18,000.
The party turned into a riot with six people injured, including two who were seriously hurt. There have been at least 20 arrests so far and it is believed at least one local store was looted.
It started off with thousands of young people in good spirits but became violent in a matter of hours.