Originally Published: 18 FEB 22 15:02 ET

Updated: 18 FEB 22 19:02 ET

By Katelyn Polantz and Zachary Cohen, CNN

(CNN) -- The National Archives acknowledged Friday it has discussed with the Department of Justice that classified records were found in boxes at Mar-a-Lago after former President Donald Trump left office, according to a letter from Archivist David Ferriero to the House Oversight Committee.

The letter, released by the Archives Friday, also provided more detail on reports that Trump tore up records after being warned not to while he was President. That letter is among four that the Archives released Friday portraying the agency, which acts as the historical library for the federal government, as concerned on multiple fronts about the Trump administration's record-keeping practices.

The Archives arranged for the transport of about 15 boxes of records from Trump's Florida resort last month after the agency sought them from the former President's team.

"NARA has identified items marked as classified national security information within the boxes," Ferriero wrote, responding to a question from the House. "Because NARA identified classified information in the boxes, NARA staff has been in communication with the Department of Justice."

The Justice Department did not immediately respond to a request for comment. CNN previously reported that the Archives had asked the Justice Department to investigate Trump's handling of White House records.

The Archives said in the Friday letter that it is "in the process of inventorying the contents of the boxes." That process is expected to be complete by February 25, Ferriero wrote.

Social media records

The Archives also said in letters to Congress Friday that some social media records and messaging on apps used by White House staff weren't properly kept as official documents despite previous warnings to Trump officials.

Among the missing records mentioned are those associated with Trump's personal Twitter account, including deleted tweets. Ferriero wrote that the Archives had previously raised concerns that Trump's deleted tweets were not being captured and was "informed by White House officials that they [were], in fact, doing so."

But since the end of the administration, the Archives said it has "learned that the White House initially used a manual process to capture tweets that were deleted from @realDonaldTrump and @POTUS," rather than the suggested automated process.

"Accordingly, we were unable to obtain a complete set of these Presidential records from the Trump Administration or Twitter. While we do have access to copies of deleted tweets collected by other non-governmental sources, we do not consider them as official Presidential records and cannot ensure the completeness of their captured account data," the letter states.

The Archives noted that it may not have a complete set of Trump tweets that would include tweets deleted from the @realDonaldTrump account between the time he took office and April 2020.

"I am advising you that the Trump Administration did not fully capture, and therefore NARA did not receive, all of the Presidential records created by President Trump and White House staff that were posted on social media platforms," Ferriero wrote in separate letters to the House Oversight Committee and the Senate Homeland Security and Governmental Affairs Committee on Friday.

The Archives also noted that it "identified seven Twitter accounts that we think contain presidential record information, but were not captured by the Trump Administration."

"These accounts belonged to Andrew Giuliani, Chad Gilmartin, Ivanka Trump, Kayleigh McEnany, Kellyanne Conway, Mark Meadows, and Peter Navarro. After the end of the administration, NARA obtained the publicly available tweets from these accounts in order to supplement its archival collection," the letter says.

The Archives also has asked Trump's representatives to search for additional records that may be missing from the government's collection, according to the letter.

In 2018, the Archives had asked a lawyer at the White House for more information about media reports at the time that Trump was tearing up documents, and that White House staff would tape them back together.

But the problem continued, the Archives told the House committee on Friday.

"The White House Counsel's Office indicated that they would address the matter," Ferriero wrote. "After the end of the Trump Administration, NARA learned that additional paper records that had been torn up by former President Trump were included in the records transferred to us. Although White House staff during the Trump Administration recovered and taped together some of the torn-up records, a number of other torn-up records that were transferred had not been reconstructed by the White House."

New York Democratic Rep. Carolyn Maloney, chair of the House Oversight Committee, said a statement Friday that the Archives' acknowledgments only deepen her concerns about the Trump administration's record-keeping habits.

"In response to my inquiry, the National Archives has confirmed that they informed DOJ of former President Trump's removal of classified material to Mar-a-Lago and that they identified additional records torn up by Mr. Trump even after the White House was warned this could violate the law," Maloney wrote.

"The National Archives also confirmed that potentially many more Trump Administration records, including direct messages sent by senior officials on multiple social media platforms, are missing. These new revelations deepen my concern about former President Trump's flagrant disregard for federal records laws and the potential impact on our historical record," she added.

A pattern of behavior

The issues that have arisen related to Trump's presidential records since he left office follow a pattern of behavior that preceded his presidency and continued during his four-year term.

Running afoul of normal preservation procedures, the then-President would often tear up documents, drafts and memos after reading them and is said to have also periodically flushed papers down the toilet in the White House residence -- only to be discovered later when repairmen were summoned to fix the clogged toilets. Trump previously denied the allegations.

Other times, the former President would task aides with carrying boxes of unread memos, articles and tweet drafts aboard the presidential aircraft for him to review and then tear to shreds.

Trump's handling of records both inside the White House and after his presidency could come under intense legal scrutiny in the coming months as congressional investigators look into the records transfer initiated by the Archives, but experts don't believe he will face criminal charges. More could potentially come to light in a spate of books about the Trump White House that are due for release this year by former White House aides and journalists who closely covered the administration.

This story has been updated with additional reporting Friday.