As stock markets see red across the globe and investors rush to the safe haven dollar, "the biggest carnage is probably in the cryptocurrency world," comments Jeffrey Halley, analyst at Oanda.

Bitcoin was plunging to an 18-month low on Monday, plagued by investors' lack of risk appetite, with the cryptocurrency market briefly falling below the symbolic $1 trillion mark. The suspension of cryptocurrency investment platform Celsius and a brief freeze on bitcoin withdrawals from the world's largest platform Binance participated in the lack of appetite for crypto-currencies. The cryptocurrency market, which was worth more than $3 trillion at its peak seven months ago, temporarily dipped below $1 trillion before climbing back up to $1,008 billion around 12:10 p.m., according to Coingecko, a site that lists more than 13,000 different cryptocurrencies.

Bitcoin's decline accelerated "after the Celsius platform 'suspended' withdrawals," notes UBS analyst Mark Haefele. The company, which managed assets valued at $12 billion in mid-May according to its website, was offering its users, among other things, to invest their "historical" cryptocurrencies, such as bitcoin and ether, in new cryptocurrencies.