UVALDE, Texas (CBSDFW.COM) -shows the chaos unfolding inside Uvalde's Robb Elementary School.
One officer can be heard asking if he's been shot.
Responding officers realized there's an active shooter.
One officer said, "I've got shots fired. They're going to be in the building on the west side. We got to get in there. We got to get in there, he keeps shooting. We got to get in there."
While clips of the video have been published previously, CBS News received multiple videos Friday lawfully through an open records request.
CBS 11 showed some of the video clips to the North Richland Hills Police Chief, Jimmy Perdue.
He serves as president of the Texas Police Chiefs Association and said the officers first on scene needed to take action that day.
"They're the ones that have the information to know there was an active shooter still going on inside that classroom and they had the greatest responsibility to take a direct action to eliminate the threat," Perdue said.
In June, the chief testified about the failed law enforcement response during a joint hearing by two Texas House committees.
As CBS 11 has reported, it took officers more than an hour to go after the 18-year-old gunman.
Chief Perdue said after initially retreating from the gunman firing shots at them, they should have gone back after him.
"The failure to go back in and re-engage at that point was a critical moment and once you don't do that initial re-engagement, then it becomes more difficult as the clocks ticks to be able to make the decision to go back in there," Perdue said.
The gunman killed 19 students and two teachers and injured 17 others.
Some people have questioned why Texas DPS didn't go in and take over the scene that day from Uvalde CISD's Police Chief Pete Arredondo.
But Chief Perdue said that's not practical or realistic.
"Because you have a lot of experience that doesn't exist within DPS that they may or may not have at DPS when they show up at the scene," Perdue said. "They understand they want to maintain local control or the control over the situation that is already in place."
On the day Chief Arredondo was fired, his attorney issued a statement saying the chief could not have served as the incident commander and didn't attempt to take that role as he was on the front line.
But Chief Perdue disagreed.
"You're the chief," Perdue said. "You're responsible for everything that goes on within your jurisdiction and in this case, that was Chief Arredondo, and he owns that responsibility regardless of where he was within the situation."
The investigations into the deadly shooting and law enforcement's response remain ongoing.
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