Authorities Review Video of Texas Church Shooting, New Details About the Attack Revealed

On Sunday, gunman Devin P. Kelley entered the First Baptist Church in Sutherland Springs, Texas, fully armed, methodically shooting victims in the head, execution-style, a law enforcement official briefed on the investigation said on Wednesday, via the New York Times.

The attack, which killed 26 people and injured 20 in the worst mass shooting in the state's history, was captured on video and reviewed by investigators. The official, who spoke on a condition of anonymity, said the shooting in the video lasted for an estimated seven minutes.

Up Next: Texas Church Shooter Was Not Welcome at Sutherland Springs Church

The official said it is not clear how many shots Kelley actually fired, although he was armed with magazines capable of holding more than 400 rounds of ammunition.

When Kelley left the church, he was shot twice by an armed bystander before fleeing in his car. He was followed by the bystander and another man before shooting himself in the head with a handgun. He was found dead after crashing his car.

Kelley had previously attended the church, and his mother-in-law was a regular member. Authorities said Kelley had an ongoing dispute with his estranged second wife's family, and his wife's grandmother was one of the people killed in the attack.

Photo Credit: Getty / Scott Olson