WASHINGTON — The Nationwide Archives confirmed on Friday that it had discovered categorised info amongst materials that President Donald J. Trump had taken with him to his dwelling in Florida when he left workplace final 12 months and that it had consulted with the Justice Division in regards to the matter.

The company “has recognized objects marked as categorised nationwide safety info throughout the containers,” in keeping with a letter posted on the Nationwide Archives and File Administration’s web site.

Final month, the archives retrieved 15 containers that Mr. Trump took with him to his Mar-a-Lago dwelling from the White Home residence when his time period ended. The containers included materials topic to the Presidential Information Act, which requires that each one paperwork and data pertaining to official enterprise be turned over to the archives.

The objects within the containers included paperwork, mementos, items and letters. The archives didn’t describe the categorised materials it discovered aside from to say that it was “categorised nationwide safety info.”

As a result of the Nationwide Archives “recognized categorised info within the containers,” the company “has been in communication with the Division of Justice,” mentioned the letter, written by David S. Ferriero, the nationwide archivist, and despatched to Consultant Carolyn B. Maloney, Democrat of New York and the chairwoman of the Home Oversight Committee, who has been scrutinizing how Mr. Trump dealt with presidential data.

Mr. Trump made attacking Hillary Clinton’s mishandling of nationwide safety supplies a centerpiece of his 2016 presidential marketing campaign. The newest revelations about Mr. Trump’s personal laxity with categorised info and his haphazard adherence to federal record-keeping legal guidelines have drawn cries of hypocrisy from Democrats.

Requested how Republicans would sq. Mr. Trump’s criticism of Ms. Clinton along with his personal report, a spokesman for the Republican Nationwide Committee, which at one point approved a resolution condemning Ms. Clinton for utilizing a personal electronic mail server whereas she was secretary of state, didn’t reply.

The New York Occasions reported final week that among the many paperwork that have been despatched again to the Nationwide Archives have been some that archivists believed have been categorised, and that the company had consulted with the Justice Division in regards to the discovery.

It isn’t clear what steps, if any, the Justice Division is taking to handle the matter.

Mr. Ferriero’s letter got here on the identical day {that a} federal choose rejected Mr. Trump’s request to dismiss three civil fits looking for to carry him to account for his function within the assault on the Capitol final 12 months. And it got here a day after a choose in New York dominated that the previous president needed to reply questions from state investigators inspecting his firm, the Trump Group, for proof of fraud.

Prior to now two weeks, a sequence of disclosures has raised new questions in regards to the Trump administration’s failure to observe federal record-keeping legal guidelines and its dealing with of categorised info as Mr. Trump left workplace.

Focusing consideration on a brand new ingredient of the problem, the Nationwide Archives mentioned in its letter on Friday that the Trump White Home had failed to show over data that included “sure social media data.”

The Trump White Home, the archives mentioned, didn’t take “any steps to seize deleted content material from any Trump Administration social media account aside from @realDonaldTrump or @POTUS.” The accounts in query included these for aides resembling Andrew Giuliani, Chad Gilmartin, Ivanka Trump, Kayleigh McEnany, Kellyanne Conway, Mark Meadows and Peter Navarro that the archives mentioned contained presidential data.

The archives additionally has not been in a position to find any of the Snapchat messages despatched by the Trump White Home.

Mr. Ferriero additionally wrote that “some White Home employees carried out official enterprise utilizing nonofficial digital messaging accounts that weren’t copied or forwarded into their official digital messaging accounts.” The archives mentioned it was within the technique of acquiring a few of these data.

Amongst these employees members was Mr. Meadows, Mr. Trump’s former chief of employees, who just lately turned over tons of of pages of paperwork to the committee investigating the Jan. 6 assault on the Capitol, a few of which got here from his private cellphone. The committee mentioned it had questions on why Mr. Meadows had used a private cellphone, a Sign account and two private Gmail accounts to conduct official enterprise, and whether or not he had correctly turned over the entire related data from these accounts to the Nationwide Archives.

Mr. Ferriero made clear in his letter that the archives had been involved for a number of years about Mr. Trump’s failure to observe the record-keeping legislation.

In June 2018, the archives “realized from an article in Politico that textual presidential data have been being torn up by former President Trump and that White Home employees have been making an attempt to tape them again collectively,” the letter mentioned.

The letter added, referring to the Nationwide Archives and Information Administration: “The White Home Counsel’s Workplace indicated that they might tackle the matter. After the tip of the Trump administration, NARA realized that extra paper data that had been torn up by former President Trump have been included within the data transferred to us. Though White Home employees in the course of the Trump administration recovered and taped collectively a few of the torn-up data, a lot of different torn-up data that have been transferred had not been reconstructed by the White Home.”

The affirmation by the archives that it had discovered categorised info within the materials might current the Justice Division with selections about how one can proceed. It might open a prison investigation into whether or not Mr. Trump and his aides mishandled categorised info, because it did in Ms. Clinton’s case.

Such an investigation could be extremely advanced, partly as a result of, as president, Mr. Trump had the power to simply declassify no matter info he wished. He might argue that he declassified the supplies he took with him earlier than he left the White Home.

No matter whether or not the bureau opens a prison investigation, it usually conducts a evaluate to find out whether or not any of the mishandled info uncovered sources and strategies, and will have broken nationwide safety.

The division might additionally select to deal with the matter as extra routine. Senior U.S. officers usually mistakenly mishandle categorised info, for instance by taking it dwelling from work or by chance utilizing it or discussing it on unsecured channels. In a lot of these situations, the F.B.I. treats the matter like “a spill” that must be cleaned up.

In these circumstances, F.B.I. brokers take a spread of measures to make sure that any nationwide safety secrets and techniques that will have been uncovered are collected to allow them to be saved on safe channels, and so they scrub, or destroy, digital gadgets the place the knowledge might have been housed or mentioned.

Mr. Trump’s dealing with of presidency paperwork has come beneath rising scrutiny. A guide scheduled to be launched in October by a Occasions reporter revealed how employees members within the White Home residence periodically found wads of printed paper clogging a rest room, main them to consider that Mr. Trump had tried to flush them.

The previous president’s use of cellphones to conduct official enterprise additionally might have led to massive gaps within the official White Home logs of his calls on Jan. 6, 2021, hindering the Home choose committee’s investigation into the Capitol riot. If Mr. Trump didn’t protect cellphone data and failed to show them over to the Nationwide Archives, that may be a violation of the legislation.

Ms. Maloney, the New York Democrat, had warned as early as December 2020 that she believed the Trump administration was not complying with the Presidential Information Act. She wrote a letter to Mr. Ferriero, the nationwide archivist, expressing what she known as “grave considerations” that the outgoing administration “might not be adequately preserving data and could also be disposing of them.”

Weeks after the Capitol riot, Ms. Maloney requested voluminous materials from the archives, together with paperwork and communications earlier than, throughout and after the Jan. 6 assault pertaining to the counting of electoral votes and deliberate demonstrations and violence.

Then, final week, Ms. Maloney announced that she was starting an investigation, after The Washington Publish reported that Mr. Trump had been destroying paperwork and shifting containers to his property in Florida as an alternative of turning them over to the archives.

Ms. Maloney mentioned on Friday that the letter from the archives “confirmed that probably many extra Trump Administration data, together with direct messages despatched by senior officers on a number of social media platforms, are lacking.”

She added, “These new revelations deepen my concern about former President Trump’s flagrant disregard for federal data legal guidelines and the potential influence on our historic report.”

Reid J. Epstein contributed reporting.