WASHINGTON (AP) — Former President Donald Trump said in a lengthy statement Monday that the FBI was conducting a search of his Mar-a-Lago estate and asserted that agents had broken open a safe.

The circumstances of the search were not immediately clear, though the Justice Department has been actively investigating the discovery of classified information in boxes of records that were taken to Trump’s Florida residence after he left the White House.

The action marks a dramatic escalation in law enforcement scrutiny of Trump and comes as he has been laying the groundwork to make another bid for president.

“After working and cooperating with the relevant Government agencies, this unannounced raid on my home was not necessary or appropriate,” Trump said in his statement.

Justice Department spokesperson Dena Iverson declined to comment on the search, including about whether Attorney General Merrick Garland had personally authorised the search.

The discovery of classified information at Mar-a-Lago was referred to the Justice Department by the National Archives and Records Administration, which said it had found classified material in 15 boxes at the residence.

Federal law bars the removal of classified documents to unauthorized locations, though it is possible that Trump could try to argue that, as president, he was the ultimate declassification authority.

There are multiple statutes governing classified information, including a law punishable by up to five years in prison that makes it a crime to remove such records and retain them at an unauthorised location. Another statute makes it a crime to mishandle classified records either intentionally or in a grossly negligent manner.

A separate investigation related to efforts by Trump and his allies to undo the results of the 2020 presidential election and the January 6, 2021, riot at the US Capitol has also been intensifying in Washington.