SUTHERLAND SPRINGS (CBSDFW.COM/AP) – Authorities say the gunman who opened fire in a Texas church had sent threatening text messages to his mother-in-law, who attended the church.

SUTHERLAND SPRINGS, TX – NOVEMBER 06: Law enforcement officials continue their investigation at First Baptist Church of Sutherland Springs as the sun begins to rise on November 6, 2017 in Sutherland Springs, Texas. Yesterday a gunman, Devin Patrick Kelly, killed 26 people at the church and wounded many more when he opened fire during a Sunday service. (Photo by Scott Olson/Getty Images)

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Texas Department of Public Safety Regional Director Freeman Martin said Monday that the mass shooting stemmed from a domestic situation and was not racially or religiously motivated.

Authorities say that evidence at the scene leads them to believe that Devin Patrick Kelley died of a self-inflicted gunshot wound after he crashed his car. He had been chased by armed bystanders.

They say Kelley also used his cellphone to tell his father that he had been shot and didn’t think he would survive.

Complete Coverage Of The Texas Church Shooting

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

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.

Kelley served in the Air Force from 2010 to 2014. He received a bad conduct discharge after he was court-martialed for assault on his wife and child. Kelley was confined by the military for 12 months. He had been living in nearby New Braunfels, where his neighbors were shocked to hear that he was the shooter.

Authorities stated Kelley was dressed in black tactical gear 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.

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