Larry Bourbannais had decided after the Columbine massacre what he would do if he were ever in a similar situation, so when shots rang out in the church he attended, the heroic Vietnam veteran acted decisively.

“I promised myself after Columbine, and I told my four daughters,  that if something like that every happened and I was there, I would go after the shooter, because you want to protect people,” the 59-year-old Bourbannais told TODAY co-host Meredith Vieira on Tuesday.

Bourbannais had been in a cafeteria in the sprawling church grounds eating a hamburger on Sunday when he heard gunshots. As others fled the church in terror, Bourbannais hurried toward the shooting scene, constantly asking, “Where’s the shooter? Where’s the shooter?”

Early on Sunday morning, Matthew Murray, 24, the home-schooled son of devoutly Christian parents, had shot and killed two people at the Youth With a Mission training center in a Denver suburb. Twelve hours later, police say, he drove to Colorado Springs and started shooting in the parking lot of the New Life church before walking inside the church building as a service was letting out, shooting as he went.

He took two more lives at the church. He was in the building when Bourbannais arrived.

“I ran and heard the gunfire and it was roaring like thunder,” Bourbannais told Vieira.

He saw a male security guard with his gun drawn, but the guard was not firing at Murray.

“I said, ‘Gimme your handgun. I’ve been in combat. I’m going to take this guy out,’ ” he said, adding he repeated the request four or five times, but the guard would not hand him the weapon.

Bourbannais was behind a pillar at the time, deciding what to do next.

“The only thing I could think to do was walk out from the pillar so the gunman would see me,” he said. “He was a man in black, but he sure wasn’t Johnny Cash.

“So I yelled, ‘Coward!’ stood out, and our eyes met and he lifted his rifle, fired, and I took a few fragments – very minor – in my left forearm.”

Bourbannais stepped behind the pillar again and repeated his demand that the security guard give him a gun so he could take the shooter out. When he got no response, Bourbannais stepped out from behind the pillar to confront Murray again.

At that point, another security guard, 42-year-old Jeanne Assam, arrived with her gun drawn. Unlike the male guard, she was using hers.

“They were engaged in a firefight. He was firing. She was firing,” Bourbannais said. “And she was completely exposed. I was in Vietnam for 14 months in combat, and it’s the bravest thing I’ve ever witnessed. She kept yelling, ‘Surrender,’ and returned fire the complete time.”

Bourbannais walked parallel to her toward Murray as Assam shot him.

“As he slumped down and his head tilted, I said to her, ‘That’s the calmest, bravest thing I‘ve ever seen. How did you do it?’ “ he said. “She said ‘I was praying and asking the Holy Spirit the entire time to guide me.’ ”

Vieira asked Bourbannais if he realized that he could have been killed.

“I figured my chances were 30 percent,” he said, as calm as if he were describing a trip to the corner store.

“It’s the grace of God,” he said. “Like Jeanne, we’re both followers of Christ. I want to give God the glory, because I’m convinced He spared us that day.”

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