A grand jury has been convened in Manhattan District Attorney Cyrus Vance’s investigation into former president Donald Trump and his company, a move that signals the two-year probe has reached a critical stage.

The grand jury is expected to decide whether to indict Trump and executives at his company, if prosecutors present the panel with criminal charges, sources told The Washington Post. This development indicates Vance’s office thinks it has found evidence of a crime, either by Trump or by someone who works for the Trump businesses.

Special grand juries such as this one are typically convened to participate in long-term matters rather than to hear evidence of crimes charged routinely. The sources say the panel was convened recently and will sit three days a week for six months. 

According to the Post, “Vance’s investigation is expansive, according to people familiar the probe and public disclosures made during related litigation. His investigators are scrutinizing Trump’s business practices before he was president, including whether the value of specific properties in the Trump Organization’s real estate portfolio were manipulated in a way that defrauded banks and insurance companies, and if any tax benefits were obtained illegally through unscrupulous asset valuation.”

The DA’s office is also reportedly examining the compensation paid out to the Trump Organization’s top executives.

A rep for Trump and an attorney for the Trump Organization did not issue a comment about the grand jury development. Trump himself continues to deny he’s done anything wrong and claims the investigation as just another political witch hunt.