The US Department of Justice (DOJ) has reportedly launched a criminal probe into whether traders are actively manipulating the price of various cryptocurrencies, including bitcoin. The probe is said to be after spoofing and wash trading.

According to Bloomberg, the move is a culmination of the US’ scrutiny into cryptocurrency markets, which some claim are rife with misconduct. Bloomberg’s report cites four people familiar with the matter.

The investigation, according to the unnamed sources, is still in its early stages and is focusing on illegal practices that can influence prices. These include spoofing the market with fake orders to trick other traders, and wash trading to create fake trading volume.

Federal prosecutors, Bloomberg adds, are working with the Commodity Futures Trading Commission (CFTC), a financial regulator, on the investigation. Notably, the CFTC is a derivatives watchdog that doesn’t regulate markets in which actual cryptocurrencies are traded. Nevertheless, it has the authority to act if it spots fraud.

The limited oversight, University of Texas finance professor John Griffin noted, makes the cryptocurrency ecosystem a target for crooks. He was quoted as saying:

“There’s very little monitoring of manipulative trading, spoofing and wash trading. It would be easy to spoof this market.”

Various cryptocurrency enthusiasts have long believed bitcoin’s price is actively being manipulated. According to CryptoCompare data, the flagship cryptocurrency has fallen from a nearly $20,000 all-time high in mid-December, to about $7,500 at press time.

The cryptocurrency’s bearish period has notably seen it various odd patterns, which some critics claim to be proof of price manipulation. Last year, a blogger known as Bitfinex’ed documented the actions of “Spoofy,” a single entity the blogger claims is dominating bitcoin’s price.

According to his work, Spoofy was a trader or group of traders that often placed orders of $1 million or more, without actually executing them. Its goal was to trick other traders and force the cryptocurrency’s price to go in the direction it wanted it to go.

As for other cryptocurrencies, it’s well-known various groups organize “pump and dump” schemes to manipulate their prices, especially when it comes to small-cap cryptos. As covered, last month a group of cryptocurrency influencers were reported to the FBI and the US Securities and Exchange Commission (SEC) for orchestrating these schemes.