A “small number” of classified documents have been found at United States President Joe Biden’s residence in the state of Delaware, the White House has confirmed, saying the files were turned over to the Department of Justice.

White House special counsel Richard Sauber said on Thursday that documents with classified markings that date back to Biden’s time as vice president were found in the garage at the now-president’s home in Wilmington, Delaware.

An additional one-page document was found in a room adjacent to the garage, Sauber said in a statement. No documents were found in Joe and Jill Biden’s second home in Rehoboth Beach, Delaware.

Sauber said the Department of Justice was “immediately notified” after the documents were located and department lawyers took custody of the records. The administration is “fully cooperating” to ensure that the records are handled properly, he said.

The discovery came days after US media outlets reported that files with classified markings from Biden’s time as vice president were uncovered in November at his former office at a think-tank in Washington, DC.

At the time, nearly 10 documents were found at the Penn Biden Center for Diplomacy and Global Engagement and were turned over to relevant authorities, the White House counsel said on Monday.

US Attorney General Merrick Garland said during a news conference on Thursday that he was appointing Robert Hur, a former US attorney in Maryland, as special counsel to investigate Biden’s handling of sensitive government documents.

“This appointment underscores for the public the department’s commitment to both independence and accountability in particularly sensitive matters, and to making decisions indisputably guided only by the facts and the law,” Garland told reporters.

“I am confident that Mr Hur will carry out his responsibility in an even-handed and urgent manner and in accordance with the highest traditions of this department.”

Al Jazeera’s Kimberly Halkett, reporting from Washington earlier in the day, said that while the Biden administration has said it has done everything it needed to do after finding the files, the discoveries have opened the White House up to criticism.

Halkett reported that Republicans have said the documents could potentially expose intelligence sources and methods and said they also reveal hypocrisy on the part of Biden, who criticised his predecessor Donald Trump for his own alleged mishandling of classified documents.

The Justice Department is investigating Trump’s handling of classified files that he retained at his personal residence in Mar-a-Lago, Florida, after leaving the White House in January 2021.

But Halkett reported that many legal experts have said the major difference between the two situations is that, when the Biden team discovered the files, they were immediately surrendered whereas US authorities needed to get a subpoena to retrieve documents from Trump’s home.

“In other words, there could be charges or prosecution [for] obstruction of justice” for the former president, Halkett said.

Trump kept thousands of government records, some of which were marked as classified, inside his Florida home and did not return them immediately or willingly despite numerous requests from the National Archives.

When he did hand over 15 boxes of records in January last year, the archives discovered more than 100 were marked as classified. It referred the matter to the Justice Department, and a special counsel has been named to oversee the investigation.

Asked on Thursday about the documents found at his Delaware home, Biden told reporters that “people know I take classified documents and classified materials seriously.” He reiterated that his administration is “cooperating fully” with the Justice Department’s review.

But the White House has refused to answer questions about why it waited more than two months to reveal the discovery of the initial batch of documents. They were found November 2, days before congressional elections.

“We did this by the book. And what I mean by that is the moment that the lawyers discovered that the papers were there, or the documents were there, they reached out to the Archives, they reached out to [the] Department of Justice,” White House Press Secretary Karine Jean-Pierre said during a news briefing on Thursday where she was peppered with questions from reporters.

“The president’s lawyers have been cooperating fully – fully,” said Jean-Pierre, adding that she was “limited” in what she could say publicly due to the ongoing investigation. She later said further questions should be referred to the White House counsel and the Department of Justice.

“He [Biden] did not know the records were there. He was surprised that the records were there,” Jean-Pierre said.

The top Republican on the House Intelligence Committee has requested that intelligence agencies conduct a “damage assessment” of potentially classified documents.

“I think Congress has to investigate this,” Republican House Speaker Kevin McCarthy told reporters on Thursday, accusing the Biden administration of hypocrisy. (Al Jazeera)

•PHOTO: US President Joe Biden says he takes 'classified materials seriously' after a second batch of files marked classified were discovered at his Delaware residence, spurring criticism [Jonathan Ernst/Reuters]

Update news