'It was a tragic failure:' active shooter trainer reacts to leaked Uvalde shooting video

Leaked footage of the Uvalde mass shooting is once again shining a light on the critical errors law enforcement made when responding to Robb Elementary School. 

An Austin newspaper has released four minutes of leaked video, showing the moments the gunman arrived at Robb Elementary School in Uvalde and how police responded. 

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Scott Stewart the VP of Torchstone Global, a company that trains corporations on how to respond to active shooters, says what the video reveals is beyond disturbing.

"It was an abject failure, and it was a tragic failure," Stewart said. 

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You can see in the video that after the gunman enters the school, he goes into a classroom, and you can hear gunshots ringing out for nearly two and a half minutes. About three minutes later, four to five officers can be seen running down the hallway toward the gunfire, but they retreated when they were fired upon.  

"That's really the point where they should've gone, engaged, and stopped the gunman," Stewart said. 

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19 minutes later, as the gunshots continued, several more officers showed up heavily armed, wearing bulletproof vests, and some carrying ballistic shields; they waited at the opposite end of the hallway as students lay dying. 

"You've got to go in, you have to stop the killing, you have to stop the dying, you can't sit outside for an hour and allow him to continue to shoot people and let people continue to bleed out," said Stewart.

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A total of 77 minutes passed before officers breached the classroom and killed the gunman, 19 children and two teachers died from gunshot wounds.

"It's going to be very difficult for them to live with themselves after this, they're going to have to carry the burden of their failure the rest of their lives," said Stewart.