In May 2021, prosecutors allege former President Donald Trump brought some of his boxes to his Bedminster, New Jersey, property. On July 21, 2021, Trump, before and during an interview for his upcoming book, showed the writer what he called "secret information" regarding national security, prosecutors said.

"Well, with [the Senior Military Official] -- uh, let me see that, I'll show you an example. He said that I wanted to attack [Country A]. Isn't it amazing? I have a big pile of papers, this thing just came up. Look. This was him," Trump said, according to prosecutors. "They presented me this--this is off the record, but—they presented me this. This was him. This was the Defense Department and him."

"Secret. This is secret information. Look, look at this," Trump said, according to prosecutors.

"See as president, I could have declassified it," Trump said, according to prosecutors.

"Now I can't, you know, but this is still a secret," Trump said, according to the indictment.

The indictment alleged that in June 2022, former President Donald Trump, after meeting with officials from the FBI and declaring himself an "open book," flew from his Mar-a-Lago home in Florida to his Bedminster, New Jersey, property with boxes of records that had been packed on his plane earlier that day.

Nauta and "others" had loaded the boxes, prosecutors said.

The indictment alleged that, after the FBI subpoenaed former President Donald Trump, he "endeavored to obstruct the FBI and grand jury investigations and conceal his continued retention of classified documents by" actions including: suggesting his attorney falsely tell the FBI and grand jury that he didn’t have documents responsive to the subpoena; directing aide Walt Nauta to move boxes of documents to conceal them from Trump’s attorney, the FBI and grand jury; and causing a false certification to be submitted to the FBI and grand jury saying all documents were provided "while knowing that, in fact, not all such documents has been produced."

The indictment noted that between January 2021 and August 2022, Mar-a-Lago hosted more than 150 social events, including weddings and fundraisers "that together drew tens of thousands of guests."

The indictment mentions five of Trump’s statements in 2016, when still a candidate for president, including when he said in August 2016 that "in my administration I’m going to enforce all laws concerning the protection of classified information."

According to the indictment, on June 2, an attorney for Trump went through the boxes in the storage room, removed 38 documents with classified markings, placed them in a redwood folder and sealed it with clear duct tape.

Trump allegedly asked, "Did you find anything?…. Is it bad? Good?" and they discussed what to do with the documents, according to prosecutors.

Trump's attorney said at that point Trump "made a funny motion as though- well okay why don't you take them with you to your hotel room and if there’s anything really bad in there, like, you know, pluck it out. And that was the motion that he made. He didn't say that."

According to the indictment, Trump and Nauta misled one of the Trump attorneys by moving boxes that contained documents with classified markings so that the attorney would not find the documents and produce them to a federal grand jury.

The indictment details how Nauta allegedly lied to FBI agents in May 2022 when he claimed to have no knowledge of the classified documents being brought to Mar-a-Lago.

The 49-page indictment against former President Donald Trump has been unsealed.

Trump has been charged with 37 counts: 31 counts of willful retention of national defense information; one count of conspiracy to obstruct justice; one count of withholding a document or record; one count of corruptly concealing a document or record; one count of concealing a document in a federal investigation; one count of scheme to conceal; and one count of false statements and representations.

The indictment alleges Trump had "lawful access to the most sensitive classified documents and national defense information gathered and owned by the United States government."

During his presidency, prosecutors said, Trump gathered classified documents and other materials in boxes, including "information regarding 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. The unauthorized disclosure of these classified documents could put at risk the national security of the United States, foreign relations, the safety of the United States military, and human sources and the continued viability of sensitive intelligence collection methods."

Trump at least twice showed classified documents to others, prosecutors said, on separate occasions in 2021 at his club in Bedminster, New Jersey.

Trump aide Walt Nauta was charged with six counts: one count of conspiracy to obstruct justice; one count of withholding a document or record; one count of corruptly concealing a document or record; one count of concealing a document in a federal investigation; one count of scheme to conceal; and one count of false statements and representations.

Prosecutors described an exchange between Nauta and an unnamed member of the Trump family shortly after Nauta allegedly removed dozens of boxes from their storage location inside Trump's Florida home, Mar-a-Lago.

On May 30, 2022, prosecutors said the Trump family member texted Nauta: Good afternoon Walt, Happy Memorial Day! I saw you put boxes to Potus room. Just FYI and I will tell him as well: Not sure how many he wants to take on Friday on the plane. We will NOT have a room for them. Plane will be full with luggage. Thank you!"

Prosecutors said Nauta replied: Good Afternoon Ma’am [Smiley Face Emoji] Thank you so much. I think he wanted to pick from them. I don’t imagine him wanting to take the boxes. He told me to put them in the room and that he was going to talk to you about them."

The indictment alleges that Nauta removed about 11 boxes from the storage room on June 1, 2022.

Former President Donald Trump can still be elected president again -- even if he is convicted -- experts tell ABC News.

But there are practical reasons that could make it a challenge, the experts told ABC News after Trump was indicted by a Manhattan grand jury in March.

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