NEW YORK (CNBC) – Former President Donald Trump filed a federal lawsuit Monday in an effort to block New York state Attorney General Letitia James from continuing to investigate his business.

James is conducting a civil probe of the Trump Organization, focusing on where the company has misstated the value of real estate assets to obtain favorable loan and insurance rates, while lowering its tax obligations.

That investigation is mirrored by a criminal investigation being conducted by the office of Manhattan District Attorney Cyrus Vance Jr.

Trump, who is a Republican, claims that both Vance and James, who are Democrats, are investigating him for political reasons, and has called the probes “witch hunts.”

The suit in U.S District Court for the Northern District of New York, which first was reported by The New York Times, argues that the investigation violates Trump’s constitutional rights.

It alleges that James’ “mission is guided solely by political animus and a desire to harass, intimidate, and retaliate against a private citizen who she views as a political opponent.”

The suit paints Trump, his family and his business as victims of a “bitter crusade” by James, who has “tirelessly bombarded” them with “unwarranted” subpoenas.

Multiple pages of the 30-page complaint are devoted to James’ tweets and past criticisms of the Trump administration.

Trump’s lawyer Alina Habba, in a written statement said, “Letitia James targets President Trump with a callous disregard for the ethical and moral obligations she swore to abide by when she became Attorney General.”

“She has short changed the state by commencing this partisan investigation and has forever tarnished the sanctity of her office,” Habba said. “By filing this lawsuit, we intend to not only hold her accountable for her blatant constitutional violations, but to stop her bitter crusade to punish her political opponent in its tracks.”

James responded to the lawsuit with the following statement;

“The Trump Organization has continually sought to delay our investigation into its business dealings and now Donald Trump and his namesake company have filed a lawsuit as an attempted collateral attack on that investigation. To be clear, neither Mr. Trump nor the Trump Organization get to dictate if and where they will answer for their actions. Our investigation will continue undeterred because no one is above the law, not even someone with the name Trump.”