Bitcoin suffered its steepest decline since January 2015 on Friday after a senior executive of China’s state-backed internet finance body said the controversial digital currency could pose risks because Bitcoins and other cryptocurrencies could be misused for illegal actions.

Li Lihui of the National Internet Finance Association of China, who previously served as the president of the Bank of China, also urged global regulators to work together to tightly supervise cryptocurrencies.

Attacking cryptocurrencies, Li said, “Digital tokens like bitcoin, ethereum that are stateless, do not have sovereign endorsement, a qualified issuing body or a country’s trust, are not legal currencies and should not be spoken of as digital currencies”.

The harsh comments of Li surfaced a day after a Chinese bitcoin platform called BTCChina declared that it would close on 30th of September and just a few hours before a second such platform announced its decision to stop operations.

In the after hours trading, Bitcoin tumbled 9.3 per cent to $3,070 in London, extending the ongoing week’s decline to a whopping 28 per cent.