Former President Donald J. Trump mentioned on Monday that the F.B.I. had searched his Palm Seaside, Fla., dwelling and had damaged open a secure — an account that, if correct, can be a dramatic escalation within the numerous investigations into the previous president.

The search, based on two individuals conversant in the investigation, gave the impression to be targeted on materials that Mr. Trump had introduced with him to Mar-a-Lago, his personal membership and residence, after he left the White Home. These packing containers contained many pages of categorised paperwork, based on an individual conversant in their contents.

Mr. Trump delayed returning 15 packing containers of fabric requested by officers with the Nationwide Archives for a lot of months, solely doing so when there turned a menace of motion being taken to retrieve them.

Mr. Trump was recognized all through his time period to tear up official materials that was meant to be held for presidency archives.

“After working and cooperating with the related Authorities businesses, this unannounced raid on my dwelling was not vital or acceptable,” Mr. Trump mentioned, sustaining it was an effort to cease him from operating for president in 2024. “Such an assault might solely happen in damaged, Third-World International locations.”

“They even broke into my secure!” he wrote. “What’s the distinction between this and Watergate, the place operatives broke into the Democrat Nationwide Committee? Right here, in reverse, Democrats broke into the house of the 45th President of the US.”

Mr. Trump didn’t share any particulars about what the F.B.I. brokers mentioned they had been trying to find. However he depicted himself as a sufferer of shadowy forces in search of to break him.

The search befell on Monday morning, an individual conversant in it mentioned, though Mr. Trump claimed brokers had been nonetheless there many hours later.

The search was at the very least partly for whether or not any data remained on the membership, the particular person conversant in the search mentioned.

The reported search got here at a time when the Justice Division has additionally been stepping up questioning of former Trump aides who had been witnesses to dialogue and planning within the White Home of Mr. Trump’s efforts to stay in workplace after his loss within the 2020 election.

Mr. Trump has been the main target of questions requested by federal prosecutors in reference to a scheme to ship “faux” electors to Congress for the certification of the Electoral School.

“These are darkish instances for our Nation, as my stunning dwelling, Mar-a-Lago in Palm Seaside, Florida, is presently beneath siege, raided, and occupied by a big group of FBI brokers,” Mr. Trump mentioned within the assertion. “Nothing like this has ever occurred to a President of the US earlier than,” Mr. Trump mentioned.