A couple who survived Sunday's mass shooting at a Texas church have provided additional, chilling details of the ordeal, including that gunman Devin Patrick Kelley went "aisle to aisle" shooting victims, including children and screaming babies, at point blank range.

Rosanne Solis and Joaquin Ramirez told a local CBS affiliate that they were seated in the last row of the church, near the doors, when they heard what sounded like firecrackers erupting outside.

Kelley then entered the church, walked to the pulpit and made his way back down the center aisle, killing church-goers at point blank range, including small children and babies. Kelley reportedly checked each aisle for survivors as he passed.

"The gunman checked each aisle for more victims, including babies who cried out amid the noise and smoke," Ramirez said.

Solis and Ramirez were able to escape by playing dead, though Ramirez told media he was hit and injured by flying debris. Many of their fellow worshippers were not so lucky; had a churchgoer not run to his truck to grab his own rifle, shooting Kelley twice and wounding him, the massacre could have claimed every life in the church, they said.

Tuesday, more details emerged about shooter Kelley, as well, including that Kelley had served time in a mental institution in 2012. Kelley escaped the hospital and tried to sneak back onto his former Air Force Base "to carry out death threats that [he] had made on his military chain of command." He was apprehended and arrested en route to base.