Jeff Lepp received a phone call during dinner on Monday night. Around 8 o’clock, an agent with the Bureau of Alcohol, Tobacco, Firearms and Explosives told Lepp they had a situation to deal with.

“You’re eating dinner with your family and your friends and all of a sudden you got to stand up and say, ‘Hey, apparently we sold the gun that belonged to a guy who just committed a mass murder in Texas,” he told 9NEWS’ sister station in Colorado Springs, KOAA.

The shooter who killed 26 people at First Baptist Church in Sutherland Springs, Texas, bought four guns on record between 2014 and 2017. Devin Kelley purchased two in Texas, and two in Colorado. One of those guns came from Lepp’s store, Specialty Sports and Supply in Colorado Springs.

“How do you actually respond to something like that other than your stomach sinks and you’re like, you got to be kidding me,” Lepp says.

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Lepp immediately left from dinner and went to work, where he and the ATF worked to trace the purchase together over the phone. The handgun the shooter purchased from Lepp’s store was not used to kill people at the church.

“At least, thank God for that. So I don’t have to think about that,” Lepp says. “But it doesn’t change the fact that the guy killed a lot of people.”

There is no reason to believe that Lepp did anything wrong. The Air Force said in a statement on Monday that they did not log a domestic abuse conviction of the shooter’s into the national system, as they’re required. Because of that, the conviction never appeared in the National Criminal Information Center Database.

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“There’s nothing to step up,” Lepp says, in terms of enhancing protocol at his shop. “Turns out there was a great deal wrong with him, but until somebody can show that, how was anybody supposed to know?”

He added, "When he purchased a firearm from us, he went through a system that does a very thorough background check but if that information hasn’t all been added into it, that’s where your shortfall comes."

Lepp says Colorado’s background check system has more strength than Texas’ because Colorado’s checks are done on both the federal and state level.

The Specialty staff has no recollection of the shooter. Lepp does say that if anyone came into his store acting inappropriately, as in drunk, or mentally unstable, the staff would ask that person to leave.

“If somebody came in and started acting in a violent way, or talking about violence, we would absolutely not have anything to do with them. We would say, ‘You have got to go,’” Lepp says.

The Air Force wrote in its statement that they’re checking other cases to make sure they have been documented properly.