More than 90 per cent of the mainland's counterfeit banknotes come from printing plates drawn by a well-known painter who is more than 70 years old. Officials from the Ministry of Public Security said that although Peng Daxiang was serving a life sentence handed down by a Guangdong court two years ago, his plates were still being used by counterfeiting gangs, the Chongqing Morning Post reported. A famous painter in his hometown of Shantou in eastern Guangdong, Peng forged food coupons that even the authorities struggled to detect. Counterfeit money is an increasing problem in China, where the face value of seized papers surged from 329 million yuan (HK$414 million) in 2012 to 532 million yuan last year. Police investigate around 1,000 cases each year. About 96 per cent of all fake money was printed on plates made by Peng, said Dong Yongxian, an official from the ministry's anti-counterfeiting laboratory. Liu Jintao, director of the anti-counterfeiting department of Guangdong Public Security Department, said it was hard to detect the crime. "A factory making counterfeits is basically a small-sized printing workshop and they can easily get printing machines, ink and commercial-use paper from the market," he said. A forged 100-yuan banknote is initially sold for 6 yuan and becomes more expensive every time it is sold, the official said. "Members of the syndicate gain huge profits, with their workers doing manual work paid at 10,000 yuan a day." In a case in an eastern Guangdong city last year, suspects had printed counterfeits weighing a tonne in less than a week. Police seized forged money with a total face value of 220 million yuan. Criminals are now forging lower-value notes, according to the head of the ministry's anti-counterfeiting department Pan Yuzong. The public were less likely to question such notes, he said.