Former President Donald Trump has been indicted by a federal grand jury on charges stemming from his efforts to remain in power after he lost the 2020 presidential election, adding to the former president's ongoing legal troubles as he mounts a third bid for the White House.

According to the indictment handed up Tuesday by a federal grand jury, Trump faces four charges: conspiracy to defraud the United States; conspiracy to obstruct an official proceeding; obstruction of and attempt to obstruct an official proceeding; and conspiracy against rights.

Special counsel Jack Smith, in announcing the charges Tuesday, called what happened on Jan. 6, 2021, an "unprecedented assault" on democracy. "It was fueled by lies: Lies by the defendant targeted at obstructing a bedrock function of the U.S. government — the nation's process of collecting, counting and certifying the results of the presidential election."

The indictment says of Trump that despite having lost, he "was determined to remain in power." So, for over two months after the election, Trump "spread lies that there had been outcome-determinative fraud in the election and that he had actually won," the indictment states, and adds, "These claims were false, and the defendant knew they were false," but "repeated and widely disseminated them anyway."

Prosecutors allege Trump and his co-conspirators also attempted to use the power of the Justice Department to conduct "sham election crime investigations," and attempted to enlist then-Vice President Mike Pence to use his ceremonial role in affirming the electoral vote count on Jan. 6 to "fraudulently alter the election results." The indictment also alleges Trump repeatedly pressured Pence to fraudulently reject or return Mr. Biden's electoral votes.

Trump has been summoned to appear at 4 p.m. ET on Thursday before Magistrate Judge Moxila A. Upadhyaya at the federal courthouse in Washington, D.C.

The indictment against Trump is the second sought by Smith in recent weeks. The former president is facing 37 federal felony counts related to his alleged mishandling of sensitive government documents retrieved from his South Florida residence, Mar-a-Lago, after he left the White House. Trump pleaded not guilty to all charges, which include conspiracy, obstruction and willfully retaining national defense information.

In addition to the now two federal prosecutions, a Manhattan grand jury indicted the former president on 34 felony counts related to alleged hush-money payments made to an adult film star before the 2016 presidential election. A trial in that case is scheduled to begin in March. New York's attorney general has brought a separate civil case against Trump and his eponymous company, with a trial set to begin in October.

Trump is also facing possible charges from the top prosecutor in Fulton County, Georgia, who has been investigating efforts to reverse the outcome of the presidential election in the state. Trump has claimed the investigation is politically motivated and denies wrongdoing.