New York’s attorney general brought a sealed lawsuit against President Donald Trump’s company, his son Eric and his personal attorney seeking to enforce an investigatory subpoena.

The secretive petition against the Trump Organization -- as well as Eric Trump and Morgan, Lewis & Bockius tax attorney Sheri Dillon -- was filed Monday in state court in Manhattan. The full complaint wasn’t immediately available.

New York Attorney General Letitia James is seeking compliance with an investigatory subpoena, according to an Aug. 21 letter to the court that was filed along with the sealed petition. Her office has kept this probe confidential to avoid undermining the investigation or causing reputational harm to the defendants or witnesses, an assistant attorney general wrote.

The attorney general’s office “has not concluded its investigation and has not reached any determination regarding whether the facts identified to date establish violations of any applicable laws,” the letter said.

James’ spokesman didn’t immediately respond to messages seeking comment on the nature of the suit. A call and email to Dillon, a partner at the law firm, weren’t immediately returned.

The secrecy around the lawsuit is unusual for James, a Democrat who has been critical of Trump and whose office successfully sued the president and his children over mismanagement of funds at Trump’s charitable organisation.