Bitcoin fell 9 percent on Friday, leaving the best-known cryptocurrency down more than 30 percent this week and headed for its worst weekly performance since April 2013.

The cryptocurrency dropped to as low as $8,155 at 0915 GMT on the Luxembourg-based bitstamp exchange amid a broader rout in the market. Other large cryptocurrencies have lost more than 20 percent of their value in the last 24 hours of trading, according to Coinmarketcap.com.

A growing regulatory backlash against digital coins has sent investors scrambling to sell this week. Bitcoin is down more than half from a December peak of almost $20,000 after it notched up a more than 1,000 gain last year.

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