An affidavit revealed 48-year-old Tam Pham was interviewed at his home in Richmond last Tuesday by agents of the FBI's Joint Terrorism Task Force.
In the document, Pham initially told agents he was in Washington for business reasons between Jan. 5 and 7, but denied taking part in the incident.
Pham agreed to hand over his cell phone to investigators who found no photos for Jan. 6. Court documents stated the agents asked to look in his "Deleted Items" folder where they found multiple pictures and videos of him inside the Capitol building.
After the agents reminded Pham that it's illegal to lie to the FBI, the documents state he admitted to entering the Capitol when others had stormed it, but denied any involvement in the violence.
Pham claimed he followed people heading to the Capitol, climbed over some fences that had already been knocked over, walked around some barriers, and never engaged with any officers present at the Capitol.
Pham told agents he went into the Capitol rotunda to look at the art on the walls and take photos, remained there for 10-15 minutes, and then left and didn't return.
The FBI affidavit stated there was probable cause to charge Pham with engaging in disorderly conduct to disrupt government business in a restricted building and engaging in disorderly conduct to disrupt a session of Congress.
PREVIOUS VIDEO: HPD officer was part of Capitol storm, chief says
Last week, Pham resigned from the Houston Police Department after 18 years on the job. He was identified by sources as the officer who traveled to Washington on Jan. 6 and "penetrated the Capitol" during the Congressional joint session to certify Joe Biden's electoral win.
He hired defense attorney Nicole Deborde to represent him in any potential criminal proceedings.
"It was more curiosity to see the President's speech with a large group of people," said Deborde. "He was curious what the President had to say. It's something that spun out of control. He's not an individual who desires to be seen at a violent protest, or an avid Trump supporter willing to stop at nothing to create a change in the election. That's not his goal at all."
RELATED: Houston police officer was part of Capitol storm, chief says
The @houstonpolice officer in question tendered his resignation this morning. The Department will release his name upon the conclusion of our joint ongoing criminal investigation with @FBI and @TheJusticeDept. https://t.co/5HlwgGuIJf— Chief Art Acevedo (@ArtAcevedo) January 14, 2021
Last Wednesday, Acevedo said he contacted the FBI special agent-in-charge of the Houston office after learning about the officer's activities. A joint investigation continues into Pham's activities that day.
During his time with HPD, Pham had no disciplinary problems, according to Acevedo.
Acevedo said he received the tip from a citizen about a Houston police officer seen in images of the Capitol siege.
While Acevedo initially said Pham traveled alone to Washington, the FBI affidavit stated Pham told agents he went to the nation's capital with his wife and her friend. All three attended the rally that preceded the storming of the Capitol, but Pham told investigators his travel companions were not with him when he followed the crowd.
RELATED: No public access to US Capitol on Inauguration day, as FBI warns of armed protests in all 50 states
Five people died during the ordeal, including a U.S. Capitol police officer.
Chaos at the Capitol: Minute-by-minute video shows how riots, violence unfolded
The FBI has received nearly 45,000 digital media tips that were being reviewed. Dozens of people and/or social media accounts of individuals who made entry into the Capitol had been identified.
The Associated Press and ABC News contributed to this report.