The FBI sought to search Donald Trump’s Mar-a-Lago resort in Florida after it found probable cause that highly sensitive national defense information and evidence of obstruction of justice existed there, according to a redacted version of the affidavit that got federal agents a warrant to search the former president’s property.

The affidavit – partially redacted by the justice department to protect details about the criminal investigation into Trump’s unauthorized retention of government secrets – offered several new details about the investigation that a top official has said remains in its “early stages”.

Here are five takeaways from the affidavit, in which the justice department also said the FBI had “not yet identified all potential criminal confederates” and “not located all evidence related to its investigation”:

New details on the probable cause

Foremost in the affidavit: the justice department had good reason to believe there were crimes being committed in specific areas of Mar-a-Lago, including Trump’s home, the foyer to his residence known as Pine Hall, his “45 Office” and a storage facility, among other locations.

The affidavit did not offer an indication about potential charges against the 45th and former president of the US, but it did mention the FBI believed that “evidence of obstruction” would be found at the premises – indicating a wider investigation than just the government’s efforts to recover sensitive documents.

New details on the FBI’s sources

Speculation has swirled for weeks around Trump and his team about how the FBI knew about the location of his safe and specific rooms where sensitive documents remained, and the justice department appeared to offer a glimpse into where that information might have originated.

The justice department said in the legal memo explaining its redactions to the affidavit that it was seeking to protect “a significant number of civilian witnesses” – the first such reference surrounding its sources – as well as other FBI and US government personnel.

Classification is irrelevant

Around the discussion in the affidavit about classified or declassified materials being retained by Trump at Mar-a-Lago, the justice department noted that classification does not matter for violations of the Espionage Act or statutes concerning the removal of official documents.

The justice department explained in a footnote that the law criminalizes “the unlawful retention of information related to the national defense” that could harm the United States or aid an adversary, regardless of whether the document is classified or declassified.

FBI’s underlying basis for concern

As part of the justification for seeking a search warrant for Mar-a-Lago, the affidavit detailed how an FBI review of materials Trump had returned to the National Archives in May 2022 demonstrated a track record of keeping some of the US government’s most sensitive secrets at Mar-a-Lago.

The justice department said among the documents recovered by the National Archives, 184 had classification markings. Some also had markings denoting “SI” for special intelligence, “HCS” for intelligence from human clandestine sources, and “NOFORN” for “Not Releasable to Foreign Nationals”.

Storage room to be secured

Some people close to Trump have tried to suggest that they were surprised that the justice department considered the storage room as inadequate to keep boxes of classified information because officials had supposedly only asked for a “stronger lock” to the door, which was installed.

However, the affidavit made no mention of a lock. In fact, it showed the justice department told Trump’s lawyer Evan Corcoran in June that Mar-a-Lago was not authorized to store classified information and asked the room be preserved in its condition until further notice – suggesting it was already the subject of an investigation.