Some of the classified documents taken by the Federal Bureau of Investigation (FBI) from former US President Donald Trump's Florida residence were discovered in his office, a court filing showed on Friday, potentially bolstering allegations that he mishandled secrets and obstructed justice.

The detailed list of what was seized in the August 8 raid on the former president's Mar-a-Lago estate also showed that Trump held on to more than 11,000 unclassified government records that he claims are his to keep - but legally are owned by the National Archives.

The list appeared to provide support for the US Justice Department's unprecedented probe.

In their warrant for the raid, the FBI cited the Espionage Act, which bans the retention and sharing of highly sensitive documents pertaining to national defense; the law against obstructing investigation; and a law against the destruction of government documents.

The violation of the Espionage Act has a possible punishment of 10 years in federal prison, the statute for obstruction carries a maximum sentence of 20 years, and the statute for the destruction of records carries a potential lifetime ban on holding public office.

Among the papers seized in the raid were 18 documents labeled "top secret", 53 labeled "secret" and another 31 marked "confidential". Of those, seven top secret files, 17 secret files, and three confidential files were retrieved from Trump's private office.

Agents also found several dozen empty folders labeled "classified" in the office, raising speculation that sensitive documents may have been lost or destroyed.

Much of what agents found there and in a separate storeroom was intermixed in boxes with Trump's personal legal files, clothing, gifts, and books tossed together for moving in his final days in the White House in January 2021.

The list was unveiled in a federal court in Florida.

On Wednesday, Trump accused the FBI of staging a scene during the raid of his Mar-a-Lago residence in Florida, claiming that they scattered documents on the floor and took pictures of them for the public.

"Terrible the way the FBI, during the Raid of Mar-a-Lago, threw documents haphazardly all over the floor (perhaps pretending it was me that did it!), and then started taking pictures of them for the public to see," Trump wrote on his Truth Social account.  

The former US President has sued the government to have the documents turned over to a neutral "special master," a move which could slow the government's investigation and possibly allow him to regain control of files he does not want made public or used in other probes.

The August raid came after 15 months of bargaining between Trump, the Archives, and the FBI over the records he took to Florida.

In January, Trump gave 15 boxes of records to the Archives, which, after discovering top secret documents mixed together, the Justice Department reported. 

Using a subpoena, top Justice officials visited the estate in June and collected another batch of classified files. But it discovered that more remained there and obtained a court warrant for the August raid.

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