NEW YORK — A New York grand jury indicted former President Donald Trump Thursday for his alleged role in a scheme to pay hush money to a porn actress during the 2016 presidential campaign, according to two people familiar with the matter.

The indictment, voted on by the grand jury Thursday afternoon and filed under seal according to the individuals, thrusts the country onto uncharted and uncertain legal and political ground.

The case against Trump, brought by the Manhattan District Attorney’s Office, is centered on a $130,000 payment to an adult film actress, Stormy Daniels, who claimed she had an affair with Trump. Trump has denied the affair. He is the first former president to ever be criminally charged.