Bitcoin prices have continued to lose steam early Tuesday, March 13.

The No. 1 cryptocurrency failed to reach its 50-day moving average of $9,920 in early trading Tuesday. Following that, bitcoin appeared unable to climb any higher and dipped back below $9,000.

Bitcoin most recently traded at $8,954.99, according to Bitstamp, the exchange which feeds prices into the CME Group futures contract. Prices have fallen about 2% for the day so far.

Prices had previously been rising to as high as about $9,900 on Sunday, March 11. Bitcoin remains well off its record high of $20,089 reached on Dec. 17, 2017. So far in 2018, bitcoin has traded as low as about $6,050 on Feb. 6, according to historical data from Coinmarketcap.

There remain a number of triggers that could be causing the plunge in bitcoin prices. Last week, the Securities and Exchange Commission warned of the "potentially unlawful" practices of some cryptocurrency exchanges, possibly stoking traders' fears of further regulation.

Additionally, traders had become concerned about sentiment after the notable influencer known as the "Tokyo Whale" sold a great deal of bitcoin holdings. The "Tokyo Whale," whose real name is Nobuaki Kobayashi, was a trustee of the now defunct Mt. Gox exchange based in Tokyo. He sold more than 35,000 bitcoin, worth about $400 million, to pay off some of creditors on behalf of the exchange.

Mt. Gox closed in 2014 and shortly after filed for bankruptcy following the theft of about 850,000 bitcoin. The "Tokyo Whale" still has about 166,000 bitcoin left to sell, but needs regulatory approval to do so.

The large-scale selling has created fears regarding supply of bitcoin on the market, but also of sentiment among some of the cryptocurrency space's biggest former proponents.

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