Rep. Elijah Cummings, the Democratic chairman of the House Oversight Committee, on Wednesday accused his Republican colleagues of obstructing the committee’s sweeping investigation into rising drug prices, after they sent letters sent to 12 drug companies urging them not to participate in the probe.

Republican Reps. Jim Jordan and Mark Meadows sent letters to a dozen top drug company CEOs earlier this month warning them not to participate in Cummings' investigation, arguing the probe is strictly partisan and suggesting Cummings is likely to leak information drug companies turn over to the committee.

“You personally may have no interest in bringing down drug prices for your constituents, you honestly may believe it is more important to protect drug company profits and stock prices than the budgets of American families, and you may even disagree with President Trump that drug companies are ‘getting away with murder’, but your efforts to interfere with this investigation represent a new low for a Member of this Committee,” Cummings wrote in a letter to Ranking Member Jordan.

“It is one thing to have an honest disagreement about the Committee’s policy or approach—which would command respect—but it is quite another to actively obstruct an investigation in the service of placing corporate interests over those of the American people,” Cummings wrote.

In their letter to the companies, Meadows and Jordan argue that Cummings released “sensitive information” as it relates to the closed-door interview of Tricia Newbold, the White House whistleblower who brought concerns over the security clearance process to the committee, attempting to make the companies fearful Cummings will do the same to them.

“To the contrary, the information released during the security clearance investigation was carefully vetted to remove sensitive information, and it accurately set forth the concerns of a career whistleblower who exhausted all other avenues to address these concerns internally,” Cummings wrote.

Jordan tweeted Wednesday that Cummings was "trying to divert attention from the classic Washington gaffe of telling the truth. He bragged about affecting “stock prices with regard to drugs.”

The issue is a top priority for Cummings. In January, he sent letters to the 12 drug companies asking for information and communications regarding “price increases, investments in research and development, and corporate strategies to preserve market share and pricing power.”

It's an effort that also has traction with President Donald Trump and thereby has the pharmaceutical industry on edge.

The administration has taken steps to crack down on this very issue.

Trump said during a 2017 Cabinet meeting that drug companies are “getting away with murder” and pledged to lower drug prices.