Former U.S. President Donald Trump holds a rally ahead of the midterm elections, in Mesa, Arizona, U.S., October 9, 2022.
The testimony of the key witness, coupled with surveillance footage the Justice Department also obtained, represent some of the strongest known evidence to date of possible obstruction of justice by the former Republican president.
The New York Times separately reported on Wednesday that Trump aide Walt Nauta was captured on security camera footage from Trump's Mar-a-Lago estate in Palm Beach moving boxes out of a storage area at the center of the investigation.
The employee who was working at Mar-a-Lago was cooperating with the Justice Department and has been interviewed multiple times by federal agents, the Post reported.
The Justice Department declined to comment on the Washington Post's report, and could not immediately be reached for comment on the New York Times article.