(NewsNation) — A second batch of classified documents belonging to President Joe Biden was reportedly discovered by White House aides, days after the discovery of documents from a former private office of the president’s became public.

The new batch was found in a separate location from the first, NBC News reported, citing a person familiar with the matter. The Associated Press also reported that a source speaking on condition of anonymity confirmed more documents were found, but did not say when or where the material was found or specific details about the level of classification.

The White House confirmed Monday that a small batch of classified records were found in an office at the Penn Biden Center in Washington, D.C., while lawyers were cleaning it out. Biden used the office from 2017 to 2019 when he was a private citizen, and the documents were reportedly from his time as vice president.

The documents were found on Nov. 2, 2022, in a “locked closet” in the office, special counsel to the president Richard Sauber said. Sauber said the attorneys immediately alerted the White House Counsel’s Office, which notified the National Archives and Records Administration — which took custody of the documents the next day.

Republicans immediately pounced on the revelation, calling for a congressional probe into the matter. The Justice Department is investigating.

During a news conference Tuesday in Mexico City, Biden said he was “surprised” to learn documents were found in the office. He told reporters “I don’t know what’s in the documents” and that his lawyers had suggested he not ask.

On Wednesday, press secretary Karine Jean-Pierre sparred with reporters over the discovery of the first batch of documents, avoiding answering questions on why the administration didn’t inform the public sooner when attorneys for Biden made the discovery on Nov. 2, just six days ahead of crucial midterm elections.

The Hill and The Associated Press contributed to this report.