Ten people have been arreated and fake banknotes with a face value of HK$300,000 have been seized.

The counterfeit money, seized in an operation code-named "Duskybee," was of poor quality but scammers used them in dark environments or in high-pressure situations to lower the chances of being found out.

Superintendent Chan Hin-kwan of New Territories orth regional headquarters said the seven men and three women, aged between 23 and 43, were arrested in Tuen Mun on Wednesday. Three are Hongkongers and the other seven are south Asians, with five holding recognizance forms.

The mastermind is believed to be a male Hong Kong identity card holder from India.

The anti-counterfeit banknote operation was conducted between October and February in connection with 17 cases. The counterfeit notes were in HK$100, HK$500 and HK$1,000 denominations.

"Scammers headed to convenience stores and shops such as those selling mobile phones during busy hours. They used the counterfeit banknotes when the sales staff were not paying full attention," Chan said, adding that some also used the notes on public transport.

"They paid taxi drivers with fake banknotes in big denominations inside the taxi's dark environment, then used various ways to distract the driver to increase their chances of using the counterfeits successfully," he said.

The ringleader got the fakes from illegal channels and sold them at one tenth of their face values to his friends.

Senior inspector Leung Cheuk-hei, also from New Territories North headquarters, said the fake notes did not carry any security features like real ones did.

"Most of them were even printed with the words 'exercise notes'," Leung said. Exercise notes are intended for bank staff members to practice counting banknotes.

Chief inspector Tang Shun-yan of the commercial crime bureau said the counterfeit notes were used across the SAR but the gang members were most active in Tuen Mun, Yuen Long, Sheung Shui and Hung Hom.

The public is reminded not to use any fake banknotes even if they receive one. The offense carries a maximum penalty of 14 years' imprisonment.

In the operation, police also found some counterfeit notes that are smaller in size than real banknotes but did not receive any reports about them.

All those arrested were detained overnight. Police did not rule out the possibility of more arrests.

The number's up for a suspect after counterfeit banknotes were seized, some sharing the same serial number.

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