North Wales Police said they used the internet to help track down six men who organised an illegal rave, where a policeman was injured.
At a special court in Pwllheli on Monday, the six admitted charges relating to organising a music event without a licence.
Hundreds turned up at Whistling Sands beach on the Lleyn Peninsula during the 2004 August bank holiday weekend.
A policeman lost his eye after being hit by a stone thrown from the crowd.
North Wales Police detectives became involved in the investigation because a police officer had been seriously injured.
It proved impossible for them to track down the individual who had thrown the stone which hit the policeman, but their investigations led to the prosecution of six men who helped arrange the event.
“The police knew about internet sites which are used by the ravers,” said Detective Constable Maldwyn Roberts, one of a team of investigating officers.
“We used pictures they had posted on one of the sites after the event, video footage from the police helicopter, and evidence we had collected when we stopped people as they left the site to bring a prosecution,” Dc Roberts added…
http://news.bbc.co.uk/2/hi/uk_news/wales/north_west/4353338.stm
