Bitcoin plunges below $12,000

The biggest and best-known cryptocurrency had seen a staggering twentyfold increase since the start of the year

Bitcoin plunged by a quarter to below $12,000 on Friday as investors dumped the cryptocurrency in manic trading after its blistering ascent to a peak close to $20,000 prompted warnings by experts of a bubble.

It capped a brutal week that had been touted as a new era of mainstream trading for the volatile digital currency when bitcoin futures debuted on CME Group, the world’s largest derivatives market on Sunday.

Friday’s steep fall bled into the US stock market, where shares of companies that have recently lashed their fortunes to bitcoin or blockchain — its underlying technology — took a hard knock