The suspect in Sunday's deadly shooting at Kingsville First Baptist Church of Sutherland Springs, Texas has been identified as Devin Patrick Kelley, 26, of New Braunfels, Texas, -- a man with a troubled, and sometimes violent past.

Kelley was court martialed from the U.S. Air Force in 2012 and CBS News initially reported that he received a dishonorable discharge. However, CBS issued a correction and then CNN later reported he received a lesser "bad conduct" discharge for assaulting his first wife and child.

He remarried in Texas in 2014. The status of that marriage was not clear, but authorities said there was a "domestic situation" with him and his in-laws. It was reported on Monday that his in-laws had attended the church.

In addition to assaulting his first wife and child, Kelley was once arrested for animal cruelty arrest and had a habit of harassing ex-girlfriends, NBC News reported.

"He was very sick in the head," Katy Landry, a former girlfriend, said. She and another woman said they were stalked by Kelley.

Police said Kelley, who was dressed in black tactical gear, opened fire with a "Ruger AR assault type rifle" before noon at the First Baptist Church, killing 26 people, including Annabelle Pomeroy, the 14-year-old daughter of church pastor Frank Pomeroy. As many as 15 others were injured in the attack.

The attack was stopped when a person at the church drew his own weapon and engaged Kelley. The person then pursued Kelley by car into an adjacent county, where the suspect ran off the road and was later found dead in his vehicle, the Los Angeles Times reported.

Law enforcement officials searched Kelley's home.

Officials said they don't believe Kelley is linked to organized terrorists, but they are looking at social media posts Kelley made before the attack, including one that showed him holding a semiautomatic weapon.

Shooting in small-town Texas church kills 26 65 Gallery: Shooting in small-town Texas church kills 26

In 2013, Kelley briefly volunteered at a vacation Bible school, The New York Daily News reported.