ATLANTA (AP) — A British filmmaker who shot interviews with Donald Trump and his inner circle in the final months of the former president’s administration has been subpoenaed to testify in a Georgia investigation into whether Trump and others illegally tried to influence the 2020 election in the state.

Footage shot by Alex Holder includes interviews from the campaign trail, as well as footage shot before and after the Jan. 6, 2021, attack on the U.S. Capitol. His lawyer, Russell Smith, confirmed Holder will appear before a special grand jury in Atlanta.

“Alex is cooperating, and he is to appear to testify on July 12,” Smith said in an email.

The special grand jury is part of an investigation by Fulton County District Attorney Fani Willis. In a letter sent to top state elected officials in February 2021, Willis said she was looking into “potential violations of Georgia law prohibiting the solicitation of election fraud, the making of false statements to state and local government bodies, conspiracy, racketeering, violation of oath of office and any involvement in violence or threats related to the election’s administration.”

The subpoena, which is dated Tuesday, also demands: “All video footage and other materials related to the docuseries ‘Unprecedented.’”

The U.S. House committee investigating the Capitol attack also subpoenaed Holder’s footage, and he said last week that he had complied with the congressional subpoena. Smith said last week that Holder sat for a two-hour deposition with the committee.

Holder has said his series had been bought by a streaming service and was to be released in three parts this summer. The hours of video footage includes exclusive interviews with Trump, his children and then-Vice President Mike Pence while on the campaign trail, Holder has said.

Willis, the prosecutor, began investigating possible illegal attempts to interfere in the state’s general election shortly after she took office in January of last year. She asked earlier this year for a special grand jury to help the investigation. The panel was seated in May and this month began hearing from witnesses, including Georgia Secretary of State Brad Raffensperger.

Willis has confirmed that her team is looking into a January 2021 phone call in which Trump pushed Raffensperger to “find” the votes needed for him to win the state. She has also said they are looking at a November 2020 phone call between U.S. Sen. Lindsey Graham and Raffensperger, the abrupt resignation of the U.S. attorney in Atlanta on Jan. 4, 2021, and comments made during December 2020 Georgia legislative committee hearings on the election.

Trump has repeatedly called his conversation with Raffensperger “perfect” and has denied any wrongdoing. Graham has also said he did nothing wrong.