US federal agents who searched ex-US president Donald Trump's Florida home this week removed 11 sets of classified documents including some marked as top secret, says Justice Department.

Receipt for property that was seized during the execution of a search warrant by the FBI at Donald Trump's Mar-a-Lago estate in Palm Beach.
Receipt for property that was seized during the execution of a search warrant by the FBI at Donald Trump's Mar-a-Lago estate in Palm Beach. (AP)

FBI agents recovered records marked "top secret" during their search of former president Donald Trump's Florida estate, according to documents made public in an investigation that includes possible violations of the US Espionage Act.

The warrant and related materials, unsealed by a Florida judge on Friday, showed agents took away with them a significant amount of classified files after the raid, which ignited a political firestorm in an already bitterly divided country.

The extraordinary search was partly based on suspicions of violations of the US Espionage Act related to the illegal retention of sensitive defence documents, the warrant showed.

Some of the papers were marked "top secret" and were "meant to be only available in special government facilities," said the unsealed seven-page federal court filing.

The filing contained a list of items removed from Mar-a-Lago, including information about the "President of France," and the warrant to search the palatial estate in Palm Beach.

READ MORE: Trump calls for 'immediate release' of Mar-a-Lago search warrant

Trump: FBI may have 'planted' docs

The Wall Street Journal said within the 20 boxes of items carted away by FBI agents were binders of photos, a handwritten note and the grant of clemency made by Trump to Roger Stone, an ally of the former president.

The Washington Post on Thursday cited anonymous sources close to the investigation as saying classified documents relating to nuclear weapons were among the papers sought during the raid.

Trump himself appeared to deny the claim, posting that the "nuclear weapons issue is a hoax" and even suggesting that the Federal Bureau of Investigation might have been "planting information" at his home.

He claimed that the documents seized by agents were "all declassified," and argued that he would have turned over the documents to the Justice Department if asked.

While incumbent presidents have the power to declassify information, that authority lapses as soon as they leave office and it was not clear if the documents in question have ever been declassified. 

Trump also kept possession of the documents despite multiple requests from agencies, including the National Archives, to turn over presidential records in accordance with federal law.

READ MORE: US agents reportedly looked for nuclear files in Trump house raid

Political storm

The highly unusual move to unseal the search warrant was announced by Attorney General Merrick Garland –– the country's top law enforcement officer –– who said he had "personally approved" the raid on Trump's home.

Leading Republicans have rallied around Trump and some members of his party have accused the Justice Department and FBI of partisanship in targeting the ex-president.

In addition to investigations into his business practices, Trump faces legal scrutiny for his efforts to overturn the results of the November 2020 election, and for the January 6, 2021 attack on the US Capitol by his supporters.

Trump was impeached for a historic second time by the House after the Capitol riot –– he was charged with inciting an insurrection –– but was acquitted by the Senate.

READ MORE: Trump invokes Fifth Amendment to evade questions over alleged fraud

Source: TRTWorld and agencies