Monday’s activity at Mar-a-Lago appears to be linked to an investigation into the potential mishandling of classified documents, according to two people familiar with the investigation.

One of the people, who spoke on condition of anonymity to discuss his details, said officers were conducting a court-authorized search as part of a long-running investigation into whether documents – including some top secrets – had been passed to the former private golf club and president’s residence instead of being sent to the National Archives when Trump left office. This could violate the Presidential Records Act, which requires retention of memos, letters, notes, emails, faxes and other written communications related to a president’s official duties.

In January, the National Archives and Records Administration recovered 15 boxes of documents and other items from Mar-a-Lago that archive officials said should have been turned over when Trump left the White House.

“The Presidential Records Act is essential to our democracy, in which government is held accountable to the people,” David S. Ferriero, then the Archivist of the United States, said in a statement in February.

At the time, Ferriero said in a statement that Trump’s representatives were “continuing to search” for additional documents. Trump resisted handing over the records for months, advisers said at the time.

Some of the documents Trump took included letters and notes from foreign leaders, such as North Korea’s Kim Jong Un.

The inventory of unclassified items in boxes recovered earlier this year from Mar-a-Lago runs to about 100 pages, according to a person familiar with the document. Descriptions of items that were incorrectly brought to Mar-a-Lago include cocktail napkin, phone list, charts, slides, letters, memos, maps, talking points, menu of birthday dinner, schedules and more, this person said. on condition of anonymity to discuss details of the ongoing investigation.