Notebooks President Biden used during his time as vice president that may reference classified information were among the material seized by the FBI during a search of his Delaware home last week, according to a report. 

The notebooks include some of the 80-year-old presidents writings related to his official White House business, such as notes on diplomatic engagements during his time as Barack Obamas vice president, according to NBC News.

While the notebooks themselves did not have classified markings, according to the report, some of Bidens handwritten notes inside them may reference sensitive material.

A person familiar with the investigation told the news outlet that the president had a large collection of notebooks with handwritten notes on both personal and official subject matter,  including his family life and his experiences or thoughts as vice president. Notebooks President Biden used during his time as vice president were among the things taken from his Delaware home. AFP via Getty Images

Because some of the notes related to official business at the White House, they could be subject to the Presidential Records Act and should have been handed over to the National Archives at the end of the Obama presidency. The latest on President Biden’s classified docs scandal Beat-up box of ‘Important Doc’s’ was out in open at Joe Biden’s house, laptop revealsFrustrated Biden has ‘no regrets’ over hiding classified docs until after midterm electionsHunter Biden wrote he quarantined at Delaware house where classified docs were stored

A person close to Biden told NBC News that it is implausible that Biden packed up the notebooks himself to be taken to his Wilmington home. 

Hes not putting anything in boxes, the anonymous individual said. The notebooks may discuss classified documents.

The FBI conducted its unprecedented 13-hour-long search of the commander in chiefs 6,850-square-foot Wilmington mansion last week, finding six more documents marked classified, some dating back to Bidens days as a senator. 

White House counsel Ian Sams described the FBIs hunt for documents as a planned consensual search in a call with reporters Monday. White House counsel Ian Sams described the FBIs hunt for documents as a planned consensual search.AP

The initial discovery of some 10 classified documents at the Penn Biden Center think tank in Washington, DC on Nov. 2 sparked the Justice Department’s investigation into Bidens mishandling of highly sensitive papers.

Before last Friday, the Justice Department decided against having FBI agents watch over searches of Bidens Delaware homes in part because Bidens attorneys were deemed to be cooperating with the DOJs investigation, the Wall Street Journal reported last week. 

Attorney General Merrick Garland appointed former Maryland US Attorney Robert Hur as a special counsel earlier this month to investigate how the classified documents ended up at Bidens namesake think tank in Washington, DC, and his home in Delaware.