The value of Bitcoin once again dropped below the $10,000 mark Tuesday after new that the United States Commodity Futures Trading Commission (CFTC) sent subpoenas to cryptocurrency exchange Bitfinex and cryptocurrency Tether.

The subpoenas were sent on Dec. 6, 2017 but were just made public by Bloomberg Tuesday morning. Bitcoin, which had been hovering around $11,000, dropped to below $10,000 for the first time in several weeks. After several hours the price did break the $10K mark again. As of 4 p.m. EST the price of bitcoin today is $10,045. 

Bitcoin Bitcoin drops below $10,000.

Bitfinex is a Hong Kong-based cryptocurrency exchange that touts itself as the “most advanced” service for cryptocurrency traders. Founded in 2012, Bitfinex is the largest cryptocurrency exchange in the world based on volume of trading.

Tether is a popular cryptocurrency that claims to have its value back directly by U.S. dollars held in reserve. The company has come under scrutiny from investors, onlookers and most recently with auditing firm Friedman, LLP .

The CTFC’s interest in both firms is likely not a coincidence; Bitfinex and Tether both share the same chief executive officer. Both companies have also provided little detail about how they operate, and have lost investor money in alleged data breaches. Bitfinex lost more than $65 million after suffering a security breach that allowed hackers to steal 119,756 bitcoin. Months later, Tether suffered a similar fate, experiencing a breach that resulted in nearly $31 million being stolen .

Both Bitfinex and Tether have essentially dismissed any concern that may arise from increased scrutiny from law enforcement. “We routinely receive legal process from law enforcement agents and regulators conducting investigations,” Bitfinex and Tether the companies said in a statement. “It is our policy not to comment on any such requests.”

However, investors appear to be less confident. While Bitcoin has spent the better part of January recovering from a sudden drop that cost the cryptocurrency about half of its value, it appeared as though it was likely to remain above the $10,000 mark—making that value its floor.

Instead, news of the CFTC’s interest in information from the major cryptocurrency exchange and popular token have caused some uncertainty within the market and resulted in a nearly 10 percent drop in value for Bitcoin Tuesday.

Nouriel Roubini, Professor at Stern School at New York University, warned on Twitter that the news could mean a crackdown on Tether is coming—news that would further drive down the value of Bitcoin.

“Indeed [Tether is] used to manipulate Bitcoin prices,” he wrote . “Without this scam Bitcoin price would collapse by 80 [percent].” Roubini said regulators have been “asleep at the wheel” while Tether’s creators have created $2 billion of fake currency with the token.