Some of Bitcoin enthusiast Mike Caldwell's coins are pictured at his office in this photo illustration in Sandy, US, on Jan 31, 2014. [Photo/Agencies]

BEIJING - The People's Bank of China (PBOC), the central bank, said Wednesday that it will continue its investigation into the country's Bitcoin exchanges.

The PBOC operations office in Beijing said in a statement that its investigators will look into payment and settlement, money laundering, foreign currency exchange, as well as information and fund security.

The decision was made based on the results of previous investigations, said the bank, without elaborating.

The PBOC sent inspection teams to major Bitcoin exchange platforms in China earlier this month, including BTCChina, the country's biggest Bitcoin trading platform, and two other major Bitcoin exchanges, Huobi and Okcoin.

Bitcoin, without ties to the bank or government, is underpinned by blockchain technology, a digital ledger system that uses cryptography.

It allows users to spend and transfer money anonymously, making the digital currency a handy tool for money laundering and capital flight.

The PBOC told investors to be aware of the risks associated with Bitcoin trading, market fluctuation and fund security, and to explore Bitcoin investment with prudence.