Two women believed to be the wife and mother-in-law of the gunman who opened fire at the First Baptist Church in Sutherland Springs, Texas, on Sunday sometimes attended the church and appear to have been close to the pastor’s family, online records and social media profiles reviewed by Yahoo News show. And police revealed on Monday that the 26-year-old gunman, Devin Patrick Kelley, of New Braunfels, Texas, sent threatening texts to his mother-in-law.

Officials say Kelley killed 26 people and wounded 20 others in what authorities say was the worst mass shooting in state history and the deadliest at any house of worship in U.S. history. Kelley was found dead following a high-speed chase that began after he was confronted by armed neighbors and fled the scene.

According her Facebook and LinkedIn accounts, Danielle Kelley (nee Danielle Lee Shields), Devin’s wife of three years, served as a vacation Bible school teacher at First Baptist Church from 2008 until 2013. Her mother, Michelle Shields, is listed as a member of the church and is seen in several Facebook photos with Sherri Pomeroy, the wife of the church’s pastor, Frank Pomeroy, and in photos and a Facebook video with Annabelle Pomeroy, the pastor’s 14-year-old daughter, who was killed in Sunday’s massacre.

Sherri and Frank Pomeroy were out of town in different states at the time of the shooting, and the service was led by a guest pastor.

Investigators work at the scene of the mass shooting at First Baptist Church in Sutherland Springs, Texas, on Sunday. (Nick Wagner/Austin American-Statesman vía AP)

At a press conference Monday morning, Texas Department of Public Safety Director Freeman Martin confirmed that Devin Kelley’s mother-in-law was a member of the church, and revealed that the gunman had “expressed anger towards his mother-in-law.”

“We can tell you there was a domestic situation going on within this family,” Martin said. “The suspect’s mother-in-law attended this church. We know that there were threatening texts from him.”

Martin said it’s not clear whether she had previously disclosed the threatening texts to law enforcement.

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“This was not racially motivated,” he added. “It wasn’t over religious beliefs.”

Yet the connections between the suspected gunman’s in-laws and the the First Baptist Church, and the suspect’s angry texts, offer the first clues about a motive for the shooting.

Wilson County Sheriff Joe Tackitt Jr. gives an update to the media at the scene of the shooting at the First Baptist Church of Sutherland Springs early Monday. (AP Photo/Eric Gay)

In television interviews earlier Monday, Wilson County Sheriff Joe D. Tackitt Jr. said that Kelley’s in-laws weren’t at the church when the shooting occurred, but that they occasionally attended services there.

“We know that his ex-in-laws or in-laws came to church here from time to time,” he said. “They were not here yesterday. So, we don’t know why he actually showed up yesterday, but we know that when he left, he left destruction.”

While it’s clear the small-town congregation was the gunman’s target, Tackitt added, authorities have yet to establish a concrete motive.

The Associated Press reported on Monday that Devin Kelley was discharged from the Air Force in 2014 for allegedly assaulting his spouse and child two years before.

On ABC’s “Good Morning America,” Texas Gov. Greg Abbott acknowledged there may have been a link between the gunman and the church, saying the public would likely be informed of such a connection “in a few days.”

“I don’t think this was just a random act of violence,” Abbott said. “Law enforcement is looking very aggressively into this.”

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