Staffordshire police swooped on illegal traders at a car boot sale on Sunday, seizing 20,000 fake game discs with an estimated street value of more than half a million pounds.
A total of 20 stalls selling illegal goods were identified at the car boot sale in Himley, Wombourne. As well as pirated games, police seized illegally copied CDs, DVDs and business software, along with 30,000 contraband cigarettes and an undisclosed number of Viagara tablets.
The most prevalent pirated game was Doom 3, which carries an adult rating. Officers also recovered a small amount of previously unseen pirated titles for GameCube.
The raid was supported by the Entertainment and Leisure Software Publishers Association (ELSPA), Staffordshire Trading Standards, the Federation Against Copyright Theft and Customs and Excise.
"This case illustrates the way in which piracy poses a threat to members of the public - allowing titles containing unregulated adult-rated content to be sold illegally without the enforcement of our rigorous ratings system, which is strictly adhered to by legitimate retail outlets," said ELSPA director general Roger Bennett.
"ELSPA would like to thank all those involved for their efforts to eradicate computer and video games piracy."
Two individuals from the West Midlands area have been reported for offences against the 1994 Trade Marks Act, and may face prosecution. The case continues.
ELSPA estimates that the cost of piracy to the UK games industry amounts to more than Â£2 billion a year. It also claims there are proven links between piracy and drug dealing, pornography and terrorism.
Anyone with information on computer games piracy is advised to contact their local police or trading standards office, or call the ELSPA anti-piracy unit hotline on 08705 133 405.