(CNN) — Special counsel Jack Smith on Thursday brought additional charges against former President Donald Trump in the case alleging mishandling of classified documents from his time in the White House.

Trump, who is already facing 37 criminal charges, was charged with one additional count of willful retention of national defense information and two additional obstruction counts, related to alleged attempts to delete surveillance video footage at his Mar-a-Lago resort in summer 2022.

Trump was charged with willfully retaining a top-secret document about possible Iran attack plans, which he discussed with biographers during a taped meeting at Bedminster, New Jersey, in July 2021, according to the indictment.

The indictment says the document was a “presentation concerning military activity in a foreign country” and that Trump “showed” it to the biographers during the meeting.

New charges were also filed against Trump’s aide Walt Nauta, and Mar-a-Lago maintenance worker Carlos De Oliveira was also added to the case. De Oliveira, 56, was charged with lying to the FBI about moving boxes with classified documents.

Trump and Nauta were previously charged last month and have pleaded not guilty.

De Oliveira was the maintenance worker who helped Nauta move boxes of classified documents around Mar-a-Lago after the Justice Department first subpoenaed Trump for classified documents last May.

CNN has previously reported that surveillance footage turned over to the Justice Department showed Nauta and De Oliveira, moving document boxes around the resort, including into a storage room just before Trump lawyer Evan Corcoran searched it for classified documents.

Justice Department officials came to Mar-a-Lago the day after Corcoran’s search, and Corcoran handed over 38 classified documents he had found. Yet the FBI retrieved more than 100 more classified documents when it searched Mar-a-Lago in August, both in the storage room and Trump’s office.

The Justice Department has subsequently said in court that it believes “government records were likely concealed and removed from the Storage Room.”

De Oliveira spoke to investigators earlier this year and his phone had been seized.

John Irving, defense attorney for De Oliveira, declined to comment.

Irving is among the lawyers whose law firm has received nearly $200,000 in payments for legal services from Donald Trump’s Save America PAC.

De Oliveira has been summoned to appear at 10:30 a.m. ET on July 31 in federal court in Miami.

In a statement, a Trump spokesman called the charges “nothing more than a continued desperate and flailing attempt by the Biden Crime Family and their Department of Justice to harass President Trump and those around him.”

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