The price of Bitcoin in China has fallen to Rmb2,950 ($475), down 17 per cent since Thursday when the Caixin report was published. Bitcoin has fallen nearly 60 per cent from its peak in November, shortly before the Chinese authorities announced the first of their measures to rein in the virtual currency's then-explosive growth in China.
Beijing ruled in December that individuals were free to buy and sell Bitcoin at their own risk. But after deeming it to be an online product rather than a currency, the government prohibited all Chinese financial institutions from conducting any Bitcoin transactions. It also barred third-party payment providers from serving Bitcoin exchanges.
Read MoreAndreessen skewers Buffett for doubting bitcoin
China's plucky Bitcoin exchanges – many of which are run by tech entrepreneurs who chafe against government regulations – thought they had found a way around the ban on payment providers. By accepting payment from customers directly in their corporate accounts, the exchanges themselves filled the gap left by payment providers and allowed people to continue buying Bitcoins.
The new central bank document threatens to end that, by preventing China's Bitcoin exchanges from even holding corporate bank accounts.
Nevertheless, an executive with one of China's leading Bitcoin exchanges, speaking on condition of anonymity, said he believed the new regulations were in draft stage and that they would not be as harsh as feared. He also said exchanges would still have workarounds if corporate accounts are closed
Read MoreIRS says bitcoin is property rather than currency
"Our core concern is whether Bitcoin is legal. The PBoC notice, if it comes, might increase transaction fees and reduce trading volume, but Bitcoin would still be legal," he said.
The regulations to date have already undercut the Bitcoin market in China, with daily transaction volumes down by as much as 80 per cent from their peak last year, according to industry estimates.
Bitcoin offered people an easy route around China's tight capital controls, and many observers believe the central bank's crackdown was aimed at reinforcing the country's defences against cross-border capital flows.