Updated January 21, 2023 at 8:24 PM ET

Officials from the Department of Justice spent more than 12 hours searching President Biden's Wilmington, Del. residence Friday, and found six new classified documents.

Biden's personal attorney, Bob Bauer, announced the extraordinary development in a Saturday night statement. The Department of Justice is declining to comment on the search.

Some of the documents date back to Biden's time as a a senator, while others were from his time as vice president, Bauer said. The DOJ also took some handwritten notes for further review, he said.

It's the latest in a series of disclosures that has raised questions about Biden's handling of classified material, and comes after the White House had said that searches of Biden's residence had been complete.

Biden has been defiant about the issue, telling reporters on Thursday that he has "no regrets" about how he and his team have handled the discovery and disclosure of the documents.

"I think you're going to find there's nothing there," Biden told reporters.

There are parallels with the Trump documents investigation

The investigation comes as the Justice Department investigates a trove of documents that former President Donald Trump took to his personal residence in Florida when he left the White House. There are now two significant parallels in the two cases.

Attorney General Merrick Garland has now appointed special counsels to investigate each of the former and sitting president's actions.

And now, both the former and sitting president's homes have been searched by law enforcement.

The Biden White House has chafed at comparisons, repeatedly emphasizing that Biden has fully cooperated while Trump repeatedly stonewalled investigators.

The White House has been selective in its disclosures about the documents

White House officials have stressed that Biden is cooperating with the investigation — even as they have repeatedly issued vague, incomplete, and at times misleading public statements about the scope of the probe.

The inquiry began after Biden lawyers found documents in a private office on Nov. 2. They found more documents in his Wilmington garage on Dec. 20, and another in his home on Jan. 11. On Jan. 14, a White House lawyer found additional material.

The Friday search of Biden's residence was kept under wraps until Saturday evening because the Justice Department requested it be private, Bauer said in his statement.

Bauer said that Biden's representatives "offered to provide prompt access" to the Department of Justice to search Biden's home for documents.

They went through decades of notes, files, memorabilia and to-do lists

Searchers, according to Bauer, went through "personally handwritten notes, files, papers, binders, memorabilia, to-do lists, schedules, and reminders going back decades" and "took possession of materials it deemed within the scope of its inquiry."

That included "six items consisting of documents with classification markings and surrounding materials," some of which dated back to Biden's time in the Senate, Bauer said. The DOJ also took some "personally handwritten notes" from Biden's time as vice president.

The search began at about 945 a.m. ET and ended about 1030 p.m. ET, and "covered all working, living and storage spaces in the home," he said.

Representatives of Biden's personal legal team and the White House Counsel's office were there.

Neither Biden nor the First Lady were in Wilmington during the search. They travel home to Wilmington on most weekends, as Biden has done throughout his time in public office. When Biden opted to instead go to his beach house in mid-January, it raised questions whether the Rehoboth Beach visit was in any way tied to the ongoing document investigation.

On Friday, Press Secretary Karine Jean-Pierre was asked directly whether the visit was in any way tied to the classified documents investigation. "He often travels to Delaware on the weekends. I just don't have anything else to share," Jean-Pierre replied. [Copyright 2023 NPR]