President Donald Trump‘s top prosecutor in Washington, D.C., has sent a letter to the nonprofit behind Wikipedia — the free online encyclopedia “anyone can edit,” according to the website — accusing it of “masking propaganda that influences public opinion” and “permitting information manipulation” in benefit of “foreign powers,” the letter says.

Ed Martin, who is the president’s nominee to oversee the U.S. Attorney’s Office for the District of Columbia, wrote that the Justice Department would be probing the “content manipulation” to see if Wikimedia Foundation was “engaging in a series of activities” that could violate its “obligations under Section 501(c)(3) of Title 26 of the United States Code,” which is what ultimately gives the organization its ability to operate as a nonprofit exempt from paying taxes.

“Wikipedia is permitting information manipulation on its platform, including the rewriting of key, historical events and biographical information of current and previous American leaders, as well as other matters implicating the national security and the interests of the United States,” Martin alleged.

“Masking propaganda that influences public opinion under the guise of providing informational material is antithetical to Wikimedia’s ‘educational’ mission,” the interim U.S. attorney said. “In addition, Wikipedia’s operations are directed by its board that is composed primarily of foreign nationals, subverting the interests of American taxpayers. Again, educational content is directionally neutral; but information received by my Office demonstrates that Wikipedia’s informational management policies benefit foreign powers.”