Bitcoin, the largest digital currency by market cap, has fallen in price by $1,400 in 12 days, going below the $5,000 threshold for the first time since October 2017.
The rout began on Wednesday and has also affected widely-traded other cryptocurrencies such as ethereum and ripple. Meanwhile, Ethereum is down 87pc from its all-time high, according to cryptocurrency news site CCN.
This is related to increasing enforcement by USA and European government authorities, as well as a new "fork" that further splinters the digital currency.
Last week, a new version of Bitcoin Cash was launched, which was itself a "fork" from the original Bitcoin blockchain. So-called alternative coins slumped even more, with Ether tumbling as much as 13 percent and Litecoin cratering as much as 14 percent.
Bitcoin continued to slide to a fresh 2018 low this morning, surpassing last week's crash as the effect of bitcoin cash's split weighed heavily on cryptocurrencies. Ripple has been doing good business lately, which is why XRP has dropped less than its peers.
Bitcoin opened trading at US$6,326, on a day that saw its market capitalisation fall to less than $100 billion for the first time in over a year.
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Bitcoin rebounded slightly to trade at US$5,035 at 1730 GMT.
"It's hardly the spirit in which many would want crypto to be used but, I'm afraid, it is what it is, and the very nature of trading means we will see this cycle over and over again".
Another clear driver is the ongoing Bitcoin Cash civil war - mining devices configured for Bitcoin Cash also serve Bitcoin, and as the former is attracting a much greater amount of network power than is usual, Bitcoin is suffering.
"We'd been waiting for a break-out", said Mati Greenspan, senior market analyst at eToro. While most of the other cryptos lost by historic margins, XRP has only dropped by a few percentages - if the cumulative figures are taken into account. Trading on futures markets, where investors can bet against Bitcoin, has soared.
The Bitcoin cash' hard fork happened as a result of the developers and miners of the coin not being able to agree on a direction for the crypto currency, leading to the creation of Bitcoin ABC and Bitcoin SV.
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