Trump indictment updates: Trump attacks special counsel after court

The federal indictment against former President Donald Trump alleges that he willfully retained documents containing the nation's most sensitive secrets, including nuclear programs, after he left office, showed some of them on at least two occasions and then tried to obstruct the investigation into their whereabouts.

Federal prosecutors allege that the classified documents included "defense and weapons capabilities of both the United States and foreign countries; United States nuclear programs; potential vulnerabilities of the United States and its allies to military attack; and plans for possible retaliation in response to a foreign attack."

Boxes of the documents were allegedly stored in locations around Trump's Mar-a-Lago club, including a ballroom stage and a bathroom, according to prosecutors.

Read the full indictment here:

Miami police officers on horseback, motorcycles and bicycles are moving into positions around the downtown federal courthouse, while the Federal Protective Service is positioning cars by the building's entrance.

A few supporters of former President Donald Trump are outside the courthouse, some carrying flags and others in costume. Some opponents are in the crowd, as well, including a man carrying a "Lock Him Up" sign.

All demonstrators at this point are peaceful.

-ABC News' Brian Hartman, Aaron Katersky and Mara Robles

Former New Jersey Gov. Chris Christie took aim at former President Donald Trump during a CNN Republican Presidential Town Hall Monday night, calling Trump's conduct "inexcusable" for someone who wants to occupy the Oval Office.

"He has shown himself, and I think most particularly in his post-presidency, to be completely self-centered, completely self-consumed, and doesn't give a damn about the American people, in my view, if what the American people want is in conflict with what Donald Trump thinks is best for him," Christie said.

"I mean, put aside taking the documents in the first place," Christie said. "But then when you start getting asked … nicely with a letter from the archivist saying, 'Could you please give it back,' and you ignore it, ignore it, ignore it. Then they come with a grand jury subpoena, and then, according to the indictment, you tell your lawyers to tell them we don't have anything even though you have dozens and dozens of boxes of material. That's obstruction of justice, if it's true."

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Former President Donald Trump is expected to be joined by his lawyers Todd Blanche and Chris Kise at Tuesday's court appearance in MIami, sources told ABC News. Meetings with additional local attorneys are ongoing.

Blanche is representing Trump in the Manhattan criminal case while Kise represents Trump and the Trump Organization in other matters.

-ABC News' Katherine Faulders, Olivia Rubin and John Santucci