Aides to US President Joe Biden have discovered at least one additional batch of classified documents in a location separate from the Washington office he used after leaving the Obama administration, a person familiar with the matter told NBC News on Wednesday. Since November, after the discovery of documents with classified markings in his former office, Biden aides have been searching for any additional classified materials that might be in other locations he used, said the source, who spoke on the condition of anonymity to provide details about the ongoing inquiry. The White House did not return a request for comment. The Justice Department had no comment. On Monday, a White House lawyer said a “small number of documents” with classified markings that are tied to Biden and appear to be from the Obama administration are under review by the Justice Department and National Archives. The documents were discovered in a locked closet by Biden’s attorneys days before the midterm elections as they prepared to vacate office space at the Penn Biden Center for Diplomacy and Global Engagement, said Richard Sauber, special counsel to the President, in a statement. CNN reported on Tuesday that among the classified documents are US intelligence memos and briefing materials that covered topics including Ukraine, Iran and the United Kingdom, according to a separate source familiar with the matter. Biden commented on the initial findings for the first time on Tuesday, telling reporters he was “surprised” that the documents were found. The President added that his attorneys “did what they should have done” when they immediately called the National Archives about the discovery. “I don’t know what’s in the documents,” he stated, saying his lawyers have suggested he not inquire what was in them. US Attorney General Merrick Garland has asked John R. Lausch, U.S. attorney for the Northern District of Illinois and a holdover Trump appointee, to review how the classified material ended up in the closet, a source familiar with the matter told NBC News on Monday. The news follows the saga of the classified documents which were discovered at former President Donald Trump’s estate in Florida, after FBI agents raided the home in August. Investigators seized 33 more boxes of records, including more than 100 documents marked classified. A report in September indicated that a document describing a foreign government’s military defenses , including its nuclear capabilities, was found by FBI agents during the search of Trump’s home. Related articles: CIA analyst admits to leaking Israel-Iran documents Reservist imprisoned for leaking documents asks for pardon NCO's wife: he acted for state good; now treated like a terrorist CIA analyst accused of Israel-Iran leak to remain in jail A subsequent report in October said some of the classified documents recovered by the FBI from Mar-a-Lago included highly sensitive intelligence regarding Iran and China. Trump insists that he declassified the documents in question before leaving office. The former President and his lawyers have publicly insinuated on multiple occasions that the agents who carried out the raid planted evidence during the search.