The search, which began at 8.30am on Wednesday and lasted until noon, was planned and conducted with the president’s consent, Bob Bauer, Biden’s personal attorney, said in a statement.

The search was the latest sign federal investigators’ probe of classified material in Biden’s possession is proceeding. FBI agents late last month found additional secret documents at the president’s Wilmington, Delaware, home, after his personal lawyers discovered documents there and at a Washington office.

“No documents with classified markings were found,” Bauer said. “Consistent with the process in Wilmington, the DOJ took for further review some materials and handwritten notes that appear to relate to his time as vice-president,” Bauer added.

The search was conducted by FBI officials, according to a person familiar who spoke on condition of anonymity. The search was planned and consensual, and was conducted without a warrant, according to the person.

Bauer, in an earlier statement, described the search as planned and occurring “with the president’s full support and cooperation”.

“Under DOJ’s standard procedures, in the interests of operational security and integrity, it sought to do this work without advance public notice, and we agreed to cooperate,” he added.

The president’s team has previously said no classified materials were discovered at Biden’s beach house in prior searches.

“No potential records were identified at the Rehoboth Beach residence” during a search conducted on January 11 by Biden’s personal attorneys, Bauer said last month in a statement. Earlier that day, the lawyers found an additional classified record at Biden’s house in Wilmington that wasn’t turned up during a search in December.

Neither the Justice Department nor the office of Special Counsel Robert Hur, who was appointed to investigate the possible mishandling of classified documents, had any comment on Wednesday’s search.

Biden’s lawyers have discovered classified documents in Biden’s Wilmington home and former think-tank office in Washington, beginning in November. The FBI searched his Wilmington home on January 20, finding more than half a dozen additional documents, some marked classified, and going back as far as his days in the Senate and his vice-presidency under Barack Obama.