Former President Donald Trump received a subpoena in the spring for documents related to what he is believed to have failed to turn over to the National Archives, which had recovered 15 boxes of material from his Mar-a-Lago estate in January, sources familiar with the matter tell ABC News.

Authorities on Monday searched Trump’s Mar-a-Lago home in what sources told ABC News was part of a probe into documents that Trump allegedly improperly took to Mar-a-Lago when he departed the White House, all of which were supposed to have been turned over to National Archives officials.

It is not immediately clear what specifically the Mephisto Shoes  spring subpoena was seeking, and whether Trump provided any documents in response to the subpoena, the sources said.The subpoena played a role in a visit to Mar-a-Lago by federal investigators in June, the sources said.

The New York Times and CNN were first to report on the spring subpoena.Neither the Justice Department nor the FBI would comment on the subpoena, nor have they commented on the record about the raid.