Trump Media & Technology Group CEO Devin Nunes is escalating his fight against Wall Street traders dealing in the company’s stock, turning to his one-time colleagues on Capitol Hill for help.

The former Republican congressman and current Trump Media CEO is pressing top House GOP lawmakers to open up investigations into what he called “anomalous trading” by professional market players betting on the stock to decline.

“There are strong indications of unlawful manipulation of DJT stock,” Nunes wrote in a letter to the lawmakers, which was disclosed Wednesday in a regulatory filing by the company — the parent of Donald Trump’s Truth Social media platform. The letter was addressed to House Judiciary Chair Jim Jordan (R-Ohio), Financial Services Chair Patrick McHenry (R-N.C.), Ways and Means Chair Jason Smith (R-Mo.) and Oversight and Reform Chair James Comer (R-Ky.).

Nunes’s letter marks a new salvo in Trump Media’s attacks on Wall Street over claims that the Trump-controlled company’s stock price is being swayed by professional traders wagering against it. Trump Media, whose stock is majority owned by the former president himself, has undergone severe price swings since debuting in the public markets late last month.

The stock initially surged as individual investors bought shares, often as a means of showing support for the presumptive GOP presidential nominee. But Trump Media, which trades on the Nasdaq stock exchange under the ticker DJT, has since plunged in value as the company has disclosed more information about its underlying financials and moved to permit some large investors to eventually cash out if they want.

Wall Street professionals, meanwhile, have raised concern about the prospects of the company’s money-losing business while traders have rushed to bet against the stock, a practice known as short selling.

Nunes asked the lawmakers to investigate the trading in Trump Media’s stock and “whether any laws including RICO statutes and tax evasion laws were violated, so that the perpetrators of any illegal activity can be held to account.” He said “a thorough and expeditious investigation” should include collecting trading data from the SEC’s massive trading database known as the Consolidated Audit Trail, the Financial Industry Regulatory Authority and the clearinghouse for U.S. stock trades.

Spokespeople for Jordan, McHenry, Smith and Comer did not immediately respond to requests for comment.

Nunes is particularly worried about a specific and illegal type of short-selling activity known as “naked short selling.”

Typical shorting involves traders borrowing shares that they then sell into the market before buying them back later — hopefully at a lower price to collect the difference. But naked short selling entails never borrowing the stock to start, a far riskier practice.

Last week, Nunes alleged in a letter to Nasdaq CEO Adena Friedman that there was “potential market manipulation” in the company’s stock from naked short selling. A Trump Media spokesperson did not immediately respond to a question on whether the company has reached out to the Securities and Exchange Commission on the issue.

Fears of naked short selling ballooned among individual investors throughout the pandemic, as day trading became a favorite pastime for many. But there is “no way to ascertain” using public data whether naked short selling is occurring in a stock, S3 Managing Director Ihor Dusaniwsky told POLITICO last week.

Trump Media’s complaints have not been well-received by the financial community. In both letters over the last week, Nunes has named four trading firms as being particularly active in the stock — including GOP megadonor Ken Griffin’s Citadel Securities. Each of the firms usually handles a substantial amount of individual investors’ trades on a given day.

A spokesperson for Citadel Securities fired back at the Nasdaq letter last week saying, “Devin Nunes is the proverbial loser who tries to blame ‘naked short selling’ for his falling price.”

Trump Media spokesperson Shannon Devine responded with a statement saying Citadel Securities is “a corporate behemoth that has been fined and censured for an incredibly wide range of offenses including issues related to naked short selling, and is world famous for screwing over everyday retail investors at the behest of other corporations.”