A Houston police officer has been arrested and charged for storming the U.S. Capitol with other Trump supporters earlier this month. According to The Texas Tribune, Tam Dinh Pham was identified through Facebook photos that linked him to rioters.

The outlet reports that it was the Houston Police Chief Art Acevedo who saw the photos and notified federal authorities. Pham agreed to meet with FBI agents and, according to an affidavit, told them that he had traveled to Washington, D.C. for his wife’s business trip.

He added that he did attend the pro-Trump rally, but denied storming the Capitol with rioters. However, federal agents found photos of Pham standing inside the Capitol rotunda in the deleted pictures folder on his phone. Pham then admitted to participating in the riot and said he spent about 15 minutes inside the Capitol, where he “looked at the historical art on the walls and took photographs and videos inside.”

Pham denied being involved with any of the far-right extremist groups that were at the riot, but said he’d learned about the gathering through Facebook and had wanted to “see history.” The affidavit shows that after listening to Trump’s speech, Pham followed the mob to the Capitol and climbed over toppled barricades and fences.

Houston Police Chief Acevedo says Pham, an 18-year veteran of the department, has resigned from his position as an officer pending the federal investigation against him. Pham was charged by federal agents with knowingly entering a restricted government building and engaging in disruptive and disorderly conduct.

According to The Appeal, over 30 police officers have been identified as pro-Trump rioters who were active in the Jan. 6 insurrection. Since the Capitol attack, police departments in Seattle, San Francisco, Pennsylvania and New Hampshire have announced investigations or terminations of officers who participated in the riot.