A U.S. official told CNN that Dennis Marx worked at the Transportation Security Administration, the federal agency that oversees airport security from October, 2002 until either 2003 or 2004.
Forsyth County Sheriff, Duane Piper said the suspected gunman, identified as Dennis Marx, shot and wounded a deputy outside a Cumming, Georgia courthouse before he was shot and killed by police.
In addition to firearms and explosives, Marx also had water and other supplies, including zip ties that can be used to bind people's hands. Piper said the wounded deputy prevented others from getting hurt when he encountered Marx, though it was not clear if that deputy killed the suspect.
"When the deputy engaged him outside, it saved lives," Piper said. "The entire situation was solved by that deputy's actions."
The Forsyth County Sheriff's office said Dennis Marx was equipped to take hostages once he got inside the north Georgia courthouse on Friday if not for the deputy who was wounded in the shootout with the gunman.
FBI, the Bureau of Alcohol, Tobacco, Firearms and Explosives, and the Georgia Bureau of Investigation agents cleared the courthouse and evacuated nearby businesses to investigate the crime scene. A no-fly zone was in effect as a bomb squad worked to secure Marx's home in Cumming, Georgia, located about 35 miles northeast of Atlanta. At least two agents with the Bureau of Alcohol, Tobacco, Firearms and Explosives, one of them a certified explosives specialist, were also on the scene, said ATF spokeswoman Regina Milledge.
Investigators are not saying what the motive may have been for Friday's shooting. However, court records evidenced that Dennis Marx had filed a civil rights complaint against the sheriff’s department in 2013, after an arrest in which he accused the Forsyth County Sheriff/s office of using excessive force and performing illegal searches.
There are unconfirmed reports that Marx was part of an anti-government movement.
Check back for details in the ongoing investigation.