Leung Yiu-chung said his office recently received reports from dozens of investors in Hong Kong who paid a total of HKD 40 million (USD 5.16 million) into the scheme run online by MyCoin, but the total loss may be vastly more.
"The number of cases is increasing. These two days I received calls about more than 30 cases. We estimate more than 3,000 people and HKD 3 billion are involved," he told AFP.
She said salespersons had told her she would recoup her investment in four months and make around 200-300 per cent profit in one year.
The cryptocurrency was created in 2009 by a computer algorithm designed by one or more anonymous people.
It has since become a form of e-money that offers a largely anonymous payment system and can be stored either virtually or on a user's hard drive.
But its development has been marred by concerns about links to illegal activities and a lack of oversight.
The value of a Bitcoin, which soared to over USD 1,200 in 2013, was around USD 285 in January.
