SUTHERLAND SPRINGS (CBSDFW.COM) – The nation is in mourning once again after 26 people were gunned down at a church service at First Baptist Church in Sutherland Springs, located just outside of San Antonio. The victims of the Sunday attack range in age from 18 months old to 77 years old.

Gov. Greg Abbott has called it the deadliest mass shooting in Texas history.

READ MORE: Grapevine Police Seek Armed Robber Who Hit Convenience Store On William D. Tate Avenue

Officials are expected to release more information about the victims sometime on Monday. Also among the dead are a woman who was pregnant and the 14-year-old daughter of the church’s pastor. Along with the 26 people who died, another 20 people were injured, including young children.

Six of the injured victims are either in stable condition or have already been released from the hospital. Four patients remain in serious condition and 10 victims are in critical condition. Because of this, authorities warned that the death toll could still increase.

Investigators identified the suspect as 26-year-old Devin Kelley. Authorities stated that he was dressed in black tactical gear with a mask featuring a skull on it, as he walked up to the church and started firing an AR-15. Kelley first shot from outside of the building, and then walked into the church to continue his attack.

Authorities explained that 23 of the deceased victims were killed inside of the church while only two people died outside of the building. One person died later at the hospital. All of the bodies have since been removed.

Kelley might have gotten away with his assault were it not for a Good Samaritan, who exchanged gunfire with the suspect as he left the building. Investigators said that a man from the neighborhood confronted Kelley as the suspect got into his car, drove a short distance, and crashed.

Johnnie Langendorff followed the suspect’s car after the Good Samaritan told him to give chase. “We hit about 95 going down 539, trying to catch this guy until he eventually lost control on his own and ended up in a ditch,” Langendorff stated. “I never got a look at him. I never really saw him. I just saw the gunfire.”

Police block a road in Sutherland Springs, Texas on November 5, 2017 after a mass shooting at the the First Baptist Church. (credit: SUZANNE CORDEIRO/AFP/Getty Images)

READ MORE: 'I Feel Like I'm Doing Something That Actually Matters' Says North Texas Mom Who Became Truck Driver Amid Nationwide Shortage

During the pursuit, Kelley notified his father that he had been shot and probably would not survive.

The suspect was found dead behind the wheel from what is believed to be a self-inflicted gunshot wound. Investigators found two additional handguns inside of the suspect’s vehicle as well. Officials are now combing over Kelley’s social media posts for anything that may provide more insight into this incident.

The exact motive for the shooting is still unknown, but Kelley’s former in-laws had attended the church “from time to time,” Sheriff Joe Tackitt said Monday. CNN also learned that Kelley’s grandmother-in-law, Lula White, was among those killed in the attack. She was a frequent volunteer at the church, according to her friends on Facebook.

Kelley had previously sent threatening text messages to his mother-in-law, however, she was not there at the time of Sunday’s shooting.

“You don’t expect to walk into a church to see something like that, especially when all the bodies are still there,” Tackitt said, remembering that horrific sight. “Seeing the children, that’s what hurts the most.”

Devin Patrick Kelley (credit: CBS News)

Kelley had been living in New Braunfels. He served in the Air Force from 2010 to 2014, but received a bad conduct discharge after he being court-martialed for assaulting his wife and child. His dishonorable discharge may have prevented him from owning a gun, but that is still under investigation. He did not have a license to carry, but did have a private security license.

Also in shock on Monday are the people who live in Sutherland Springs, a small community of only 638 people. This has been a devastating loss for those residents, many still in disbelief over what transpired on Sunday. One out of every 25 people in the community were killed during this attack. Hospitals in San Antonio are asking for blood donations on Monday.

MORE NEWS: Tarrant County Prosecutor Chris Taylor Appointed Judge For Texas' 48th District Court

Kevin Joran witnessed the shooting. He added, “It’s sad because… why this church? Why the people that I grew up with? Why them? It’s hard.”