Kelley was once a member of the US Air Force, spokeswoman Ann Stefanek said. He served in logistics readiness at Holloman Air Force Base in New Mexico, starting in 2010.
Kelley was court-martialed in 2012 for two counts of Article 128 of the Uniform Code of Military Justice, assault on his spouse and assault on their child, Stefanek said. Kelley received a bad conduct discharge, confinement for 12 months and a reduction in rank, she said. The Air Force did not provide a date of the discharge.
Kelley is accused of killing 26 people, including the 14-year-old daughter of the church's pastor, and injuring more.
A man who lives next door to the church grabbed his own gun and approached Kelley as he was leaving after the shooting. The gunman dropped a rifle in front of the church and fled in his car, officials said.
Kelley was found dead in his car from a gunshot wound about eight miles from the church, according to a law enforcement official. It's not clear if he shot himself or if the neighbor shot him.
Kelley purchased the Ruger AR-556 rifle in April 2016 from an Academy Sports & Outdoors store in San Antonio.
When Kelley filled out the background check paperwork at the store, he checked the box to indicate he didn't have disqualifying criminal history, the official said. He listed an address in Colorado Springs, Colorado when he bought the rifle, the official said.
