Some money changers in Hong Kong are refusing to accept 100 yuan banknotes with serial numbers starting with HD90 as panic over fake mainland notes spills over the border. Hong Kong police said yesterday that they were staying in close contact with their mainland counterparts to keep updated on the issue. Yesterday, some money changers in Hong Kong put up notices at their shops saying suspect 100 yuan banknotes would not be accepted. A Sham Shui Po money changer said: 'To play it safe and to protect our interests, we are not accepting 100 yuan notes with serial numbers starting with HD90.' Local media reported yesterday that more high-quality counterfeit 100 yuan notes had been found in some major mainland cities, including Guangzhou and Shanghai. Quoting mainland media reports, RTHK said many Guangdong residents had bought the fake notes via websites. One Hong Kong man said he believed he had been given a fake note by a money changer in Kwai Chung. The man told Cable TV that he had wanted to use the note to make a purchase in Shenzhen but was told by the shopkeeper it was fake. The People's Bank of China said on Thursday that there was no cause for panic. It said the fakes were easily distinguishable from genuine notes. The mainland's central bank said some notes with HD90 in their serial numbers were genuine and serial numbers alone could not be used to determine authenticity. It also said the public could tell whether a note was genuine or not from its security fibres, security thread and watermark. Edwin Shiu Man-chak, of Ngau Kee Money Changer in Sheung Wan, said: 'The problem does not seem to be as serious here as in China. So far we have not found any fake 100 yuan banknotes. But we shall be on alert.' Mr Shiu said he had confidence in his cash detectors and that his experienced staff could tell whether a note was fake or not by touch. According to police figures, 7,975 counterfeit yuan banknotes were seized in the first nine months of last year, up 21 per cent from the same period in 2007. Last Sunday, two mainland men were arrested when they attempted to make a purchase in a Tsim Sha Tsui shop using fake yuan notes. Police seized 13 counterfeit 100 yuan notes, which were reportedly of high quality and with similar serial numbers.