A "significant number of printing plates" were seized in the raid, according to a City of London Police spokesman.

The spokesman said the plates were allegedly involved in the production of printed covers for counterfeit DVDs, including recent hit films such as Slumdog Millionaire and The Curious Case of Benjamin Button.

Four people were arrested in connection with the production, distribution of counterfeit DVD covers and money laundering. They have since been released on police bail, it is not currently clear if they are employees of the company.

BDP (UK), which is located in Ironbridge Business Park, has not returned PrintWeek's calls.

FACT (Federation Against Copyright Theft) alleged that the commercial business has printed millions of covers over the past year.

The operation followed what is thought to be a related raid at a DVD-making factory in Southall, West London in February. This resulted in the arrest of five people and the seizure of large quantities of copying equipment and discs.

City of London Police detective chief inspector Dave Service said: "This operation provides further evidence of the scale of the organised criminal networks involved in DVD counterfeiting and how big a problem it has become."

Kieron Sharp, FACT director general, said the factory in Southall could have been capable of generating a criminal profit in excess of £1m per week.