High school classmates of Devin Patrick Kelley, the suspect in Sunday's mass shooting in Sutherland Springs, Texas, described the 26-year-old man as a depressed atheist who railed against God online.

"He was the first atheist I met. He went Air Force after high school, got discharged but I don't know why," Patrick Boyce, who attended New Braunfels High School with Kelley, and others told the Daily Mail.

"I was just shocked [to hear the news]. Still haven’t quite processed how he could have done that," Boyce added. "He had a kid or two, fairly normal, but kinda quiet and lately seemed depressed."

Another former schoolmate, Nina Rose Nava, said she had just deleted the 26-year-old man as a friend on Facebook because of his posts.

"I legit just deleted him off my fb cause I couldn't stand his post," Nava wrote. "He was always talking about how people who believe in God we're stupid and trying to preach his atheism."

Christopher Leo Longoria responded to Nava and said he "removed him off FB for those same reasons."

"He was weird but never that damn weird, always posting his atheist sh** like Nina wrote, but damn he always posted pics of him and his baby — crazy," Michael Goff wrote.

Kelley was married to Danielle Shields, who had previously served as a Sunday school teacher at the First Baptist Church, where Kelley is believed to have carried out the shooting, Daily Mail reported.

He had been licensed by the Texas Department of Public Safety as a secretary guard, according to the state website.