Biden ‘Surprised to Learn’ Classified Obama-Era Documents Were Found in Former D.C. Office

President Joe Biden said Tuesday that he was “surprised” to learn government documents were found at his former Washington, D.C. office space.

Speaking at a news conference in Mexico, the president said his attorneys “did what they should have done” in turning over the “small number” of documents that were found in a locked closet in November at the Penn Biden Center for Diplomacy and Global Engagement.

“They immediately called the (National) Archives, turned them over to the Archives, and I was briefed about this discovery and surprised to learn that there were any government records that were taken there to that office,” Biden said during his visit with Mexican President Andrés Manuel López Obrador.

“I don’t know what’s in the documents, my lawyers have not suggested that I ask what documents they were,” added Biden. “I’ve turned over the boxes, they’ve turned over the boxes to the archives.”

“We’ve cooperated fully with the review, which I hope will be finished soon.”

The documents were returned to the National Archives the day after they were found, according to White House counsel Richard Sauber.

RELATED: Biden’s Team Returns ‘Small Number’ of Classified, Obama-Era Documents Found in Former D.C. Office

US President Joe Biden speaks during a Hanukkah Holiday Reception in the Grand Foyer of the White House

Samuel Corum/UPI/Shutterstock Joe Biden

CBS News was first to report on the documents, which are now being reviewed by a U.S. attorney in Chicago at the direction of Attorney General Merrick Garland.

The attorney general may appoint a special counsel to further handle the matter, The New York Times reported.

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While the documents did not contain nuclear secrets like those found at former President Donald Trump’s Mar-a-Lago property in Florida, they did include briefing materials about foreign countries during Biden’s tenure as vice president, sources told The Times.

joe biden

Yuri Gripas/Abaca/Bloomberg via Getty Images President Joe Biden

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RELATED: Donald Trump Had ‘More than 300’ Classified Documents at Mar-a-Lago: Report

Unlike the Mar-a-Lago documents, the newly discovered items also had not previously been the subject of any inquiries by the National Archives, according to Sauber.

On Tuesday, Rep. James Comer, the new chair of the House Oversight Committee, told CNN he would be sending a letter to the Archives within the next 48 hours regarding the matter.

“President Biden has been very critical of President Trump mistakenly taking classified documents to the residence or wherever and now it seems he may have done the same,” Comer said. “How ironic.”

The Associated Press reported that the letter requests copies of the documents, as well as any communications about the discovery and a list of those who could have had access to the think tank office where they were found.