WASHINGTON: The FBI on Wednesday conducted a search operation of Joe Biden Delaware residence as a part of its investigation into the potential mishandling of classified documents, the president’s lawyer said. A three-hour-long search operation was conducted where no documents with classified markings during a three-and-a-half-hour search of Biden’s beach house but did take some materials for further review.

Biden’s personal attorney Bob Bauer said in a statement that Wednesday’s search took place from 8:30 AM to noon in “coordination and cooperation with the president’s attorneys” and had been planned.

“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 said.

The search by FBI agents appears to represent an expansion of the probe into Biden’s handling of classified documents. Earlier incriminating documents were found at his home in Wilmington, Delaware, and an office he used during the time between his service as vice president under Barack Obama and his presidential election. Classified documents have also been found in the home of Trump’s former vice president, Mike Pence, giving some political cover to Biden.

The issue has created a political headache for Biden, who is expected to undergo a re-election campaign in the coming weeks or months. It has stripped him and fellow Democrats of a weapon against former President Donald Trump, who also had classified documents found at his home.

Trump has launched his own re-election campaign and could face Biden in the 2024 general election.

Meanwhile, the National Archives has reportedly asked all former U.S. presidents and vice presidents to search their personal records for classified documents or other presidential material that should have been turned over when they left office.