(NewsNation) — The tightly knit Uvalde community is mourning the loss of some of its youngest residents. The investigation continues after 19 children and two adults were killed at the Texas elementary school Tuesday.

A Border Patrol agent shot and killed the 18-year-old gunman, ending the violent rampage. In the video above, former police officer and FBI hostage negotiation expert Adam Davis talks about the agent’s actions.

“What you see is the fruit of someone who is prepared for the moment of truth. They are highly trained, very specialized for high-risk situations. And it requires a lot of courage and a very specialized set of skills to be able to do (what) that Border Patrol agent did yesterday, which is stop what could have been … dozens more killed,” Davis said.

“You know” Davis said, ‘it’s heartbreaking what’s going on, but I think you need to honor the heroism of these men or women who’ve jumped in and stopped it from being any worse.”