Montgomery County Precinct 3 Constable's Office told Eyewitness News that the suspect is not an officer but works for the bureau.
The suspect, Garrett Wilson Anderson, is facing 10 charges related to child pornography, including possession and intent to distribute.
His bond hasn't been set at this time.
ATF told Eyewitness News that Anderson worked as an administrative support employee for the agency, saying they expect all workers to maintain high ethics.
"ATF takes allegations of criminal misconduct seriously. ATF employees are held to a high standard of conduct and are expected to maintain the highest ethics in both their professional and private lives," the federal agency said in a statement to ABC13.
Anderson's employment status with the bureau following his arrest is unclear.