US President Joe Biden's aides found more classified documents from his time as vice president at a second location, news organisations reported on Wednesday, deepening a political and potential legal case.
Some documents with classified labels were found in November at an undisclosed space that Mr Biden used after his work in former president Barack Obama's administration.
NBC News first reported the new finding by Mr Biden's team.
CNN and The New York Times also report that it is not known what level of classification the files had or where they were found.
The second set of material was found as part of a search after CBS News reported on Monday that almost 10 classified files were discovered at the former vice president's office at the Penn Biden Centre for Diplomacy and Global Engagement, also in November.
"I was briefed about this discovery and surprised to learn that there were any government records that were taken there to that office," Mr Biden said on Tuesday.
"But I don’t know what’s in the documents."
The White House said the documents were immediately handed to the National Archives and Records Administration.
The Department of Justice is now reviewing the situation, the White House shared after Monday's report.
"And we’re co-operating fully with the review," Mr Biden said.
The disclosure of possibly mishandled sensitive documents is a boon for the Republican Party, which is looking to push back against the Biden administration with its slim House majority.
It comes after a potential espionage case in which former president Donald Trump became involved when the FBI found about 100 classified documents in a court-approved search at his private residence.
