UVALDE, Texas – The horrific scope of an elementary school shooting that killed 19 children and two teachers was coming into agonizing focus Thursday amid new revelations about the attack, including that the gunman barricaded himself in a fourth grade classroom where most victims died.

Some community members who had gathered outside Robb Elementary School as the drama unfolded urged police officers to charge in. “Go in there! Go in there!” nearby women shouted at officers soon after the attack began, said Juan Carranza, 24, who saw the scene from outside his house. The officers did not immediately enter the building, he said.

Department of Public Safety Director Steve McCraw said a Border Patrol tactical team shot the gunman 40 minutes to an hour after he opened fire on a school security officer.

“The bottom line is law enforcement was there,” McCraw said. “They did engage immediately. They did contain (the gunman) in the classroom.”

Javier Cazares, whose fourth-grade daughter, Jacklyn Cazares, was killed in the attack, said he arrived at the scene while police were still gathered outside the building. Upset that police were not moving in, he raised the idea of charging into the school with several other bystanders.

“Let’s just rush in because the cops aren’t doing anything like they are supposed to,” he said. “More could have been done.”

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‘Hearts are forever shattered’

As officials work to piece together what happened, grieving residents tried to comprehend the unimaginable loss and console friends and neighbors. In Uvalde, a South Texas city of 16,000 residents, nearly everyone knew a family touched by the bloodshed – either directly or indirectly. Texas Gov. Greg Abbott said 17 other people were wounded, and that the parents of each victim had been informed of their deaths.