Three people have been arrested and 810 fake cards seized after police uncovered a counterfeit credit card manufacturing plant in two public housing flats in Wong Tai Sin. Circulation of the fake cards could have cost the industry up to $20 million, officers said. A computerised production system - the first of its kind found in Hong Kong - was being used to make the fake cards, said Chief Superintendent Vincent Wong Fook-chuen, head of the Commercial Crime Bureau. 'Our investigation revealed that bogus credit cards would be used for spending sprees in Hong Kong and overseas. We believe that each fake card would be sold for between $2,000 and $3,000 to buyers,' he said. Officers estimated that each bogus credit card had an average spending limit of US$3,000. 'So if all the seized fake credit cards are used on a spending spree, there is a potential for losses of up to $19.7 million for the credit card industry,' Superintendent Kwok Ho-fai said. Mr Wong said the high quality of the bogus cards made it difficult for people to realise they were fake and some could already be circulating in the market. The arrests were made at noon on Tuesday when 20 officers raided the flats in Chuk Yuen South Estate. Police arrested a man, 45, and seized the 810 finished and unfinished bogus credit cards and a various equipment for producing fake cards, including an embossing machine, printing machine, a skimmer and computer in one of the units. Another team raided another unit in the same block and arrested a man, 47, and a woman, 39. The man is alleged to be the mastermind of the gang. Inside the second unit, a notebook containing credit card account information and another two computer laptops were seized. Mr Wong said the account data was mainly from Europe and North America. Investigations revealed the blank cards were made on the mainland and smuggled into Hong Kong by couriers. Detectives are still investigating how the syndicate obtained the credit card account data. Police said the counterfeiting machines they usually seized were operated manually but in this case the equipment was connected to a computer. Mr Wong said the bureau had been monitoring the syndicate since October. It was not known how long it had actually been in operation. He said it was the largest single source of bogus credit cards found in recent years. In 2002, 710 fake cards were seized at another 'factory'. Last night, the three suspects who were arrested for possessing equipment for making a false instrument remained in custody but no charges had been laid.